EE to CE migration issue

I have been so long trying to update properly without success is there any way to fix migrations or do I have to remove gitlab altogether to fix this issue, my instance is constantly showing 500 Error page now.

[root@git ~]# gitlab-rake db:migrate == 20190402150158 BackportEnterpriseSchema: migrating ========================= -- table_exists?(:epics) -> 0.0009s -- column_exists?(:epics, :parent_id) -> 0.0058s -- table_exists?(:geo_event_log) -> 0.0006s -- column_exists?(:geo_event_log, :cache_invalidation_event_id) -> 0.0022s -- table_exists?(:vulnerability_feedback) -> 0.0006s -- column_exists?(:vulnerability_feedback, :merge_request_id) -> 0.0019s rake aborted! Exception: Your database is missing the 'merge_request_id' column from the 'vulnerability_feedback' table that is present for GitLab EE. Even though it looks like you're running a CE installation, it appears you may have installed GitLab EE at some point. To migrate to GitLab 12.0:

Install GitLab 11.11.3 EE
Install GitLab 12.0.x CE

/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:916:in `raise_ee_migration_error!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:896:in `check_ee_columns!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:888:in `block in check_schema!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:887:in `each'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:887:in `check_schema!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:120:in `up'
/opt/gitlab/embedded/bin/bundle:23:in `load'
/opt/gitlab/embedded/bin/bundle:23:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)
[root@git ~]# gitlab-rake db:migrate --trace
** Invoke db:migrate (first_time)
** Invoke db:load_config (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:load_config
** Invoke schema_version_check (first_time)
** Invoke environment
** Execute schema_version_check
** Execute db:migrate
== 20190402150158 BackportEnterpriseSchema: migrating =========================
-- table_exists?(:epics)
   -> 0.0011s
-- column_exists?(:epics, :parent_id)
   -> 0.0060s
-- table_exists?(:geo_event_log)
   -> 0.0007s
-- column_exists?(:geo_event_log, :cache_invalidation_event_id)
   -> 0.0023s
-- table_exists?(:vulnerability_feedback)
   -> 0.0007s
-- column_exists?(:vulnerability_feedback, :merge_request_id)
   -> 0.0020s
rake aborted!
Exception: Your database is missing the 'merge_request_id' column from the 'vulnerability_feedback' table that is present for GitLab EE.
Even though it looks like you're running a CE installation, it appears
you may have installed GitLab EE at some point. To migrate to GitLab 12.0:

1. Install GitLab 11.11.3 EE
2. Install GitLab 12.0.x CE
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:916:in `raise_ee_migration_error!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:896:in `check_ee_columns!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:888:in `block in check_schema!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:887:in `each'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:887:in `check_schema!'
/opt/gitlab/embedded/service/gitlab-rails/db/migrate/20190402150158_backport_enterprise_schema.rb:120:in `up'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:817:in `exec_migration'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:798:in `block (2 levels) in migrate'
/opt/gitlab/embedded/lib/ruby/2.6.0/benchmark.rb:293:in `measure'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:797:in `block in migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:416:in `with_connection'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:796:in `migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:977:in `migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1292:in `block in execute_migration_in_transaction'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1345:in `ddl_transaction'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1291:in `execute_migration_in_transaction'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1263:in `block in migrate_without_lock'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1262:in `each'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1262:in `migrate_without_lock'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1210:in `block in migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1363:in `with_advisory_lock'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1210:in `migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1036:in `up'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/migration.rb:1011:in `migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/tasks/database_tasks.rb:172:in `migrate'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/activerecord-5.2.3/lib/active_record/railties/databases.rake:60:in `block (2 levels) in <top (required)>'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:273:in `block in execute'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:273:in `each'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:273:in `execute'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:214:in `block in invoke_with_call_chain'
/opt/gitlab/embedded/lib/ruby/2.6.0/monitor.rb:230:in `mon_synchronize'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:194:in `invoke_with_call_chain'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/task.rb:183:in `invoke'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:160:in `invoke_task'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:116:in `block (2 levels) in top_level'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:116:in `each'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:116:in `block in top_level'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:125:in `run_with_threads'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:110:in `top_level'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:83:in `block in run'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:186:in `standard_exception_handling'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/lib/rake/application.rb:80:in `run'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/rake-12.3.2/exe/rake:27:in `<top (required)>'
/opt/gitlab/embedded/bin/rake:23:in `load'
/opt/gitlab/embedded/bin/rake:23:in `<top (required)>'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli/exec.rb:74:in `load'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli/exec.rb:74:in `kernel_load'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli/exec.rb:28:in `run'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli.rb:463:in `exec'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/vendor/thor/lib/thor.rb:387:in `dispatch'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli.rb:27:in `dispatch'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/vendor/thor/lib/thor/base.rb:466:in `start'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/cli.rb:18:in `start'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/exe/bundle:30:in `block in <top (required)>'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/lib/bundler/friendly_errors.rb:124:in `with_friendly_errors'
/opt/gitlab/embedded/lib/ruby/gems/2.6.0/gems/bundler-1.17.3/exe/bundle:22:in `<top (required)>'
/opt/gitlab/embedded/bin/bundle:23:in `load'
/opt/gitlab/embedded/bin/bundle:23:in `<main>'
Tasks: TOP => db:migrate
[root@git ~]#

Edited Nov 13, 2020 by Nicole Schwartz