Inconsitent Merge Request State

Summary

A MR was merged, but Gitlab claims it failed.

Steps to reproduce

Unsure, create a new MR and hope it fails?

What is the current bug behavior?

The MR was sucessfully merged in the repository (as visible when cloning), but the web view still sees an open phantom MR. The MR it self also states that it was merged and that it wasn't merged.

The checkbox for delete source branch was set prior to merging, but that has apparently also failed.

What is the expected correct behaviour?

Merging an MR should either fail completely, or succeed completely.

Relevant logs and/or screenshots

screen2

I scanned through the logs and found no errors. Which one should contain one?

Results of GitLab environment info

System information
System:         Debian 10
Current User:   git
Using RVM:      no
Ruby Version:   2.6.3p62
Gem Version:    3.0.3
Bundler Version:1.17.3
Rake Version:   12.3.3
Redis Version:  5.0.3
Git Version:    2.24.1
Sidekiq Version:5.2.7
Go Version:     go1.13.5 linux/amd64

GitLab information
Version:        12.6.4-ee
Revision:       c3e911be175
Directory:      /var/git/gitlabhq
DB Adapter:     PostgreSQL
DB Version:     12.1
URL:            
HTTP Clone URL: 
SSH Clone URL:  
Using LDAP:     no
Using Omniauth: no

GitLab Shell
Version:        10.3.0
Repository storage paths:
- default:      /var/git/repositories
GitLab Shell path:              /var/git/gitlab-shell
Git:            /usr/local/bin/git

Results of GitLab application Check

Expand for output related to the GitLab application check 
Checking GitLab subtasks ...                                                                                                                                                                                                                                                                                                

Checking GitLab Shell ...


GitLab Shell: ... GitLab Shell version >= 10.3.0 ? ... OK (10.3.0)

Running /var/git/gitlab-shell/bin/check

Internal API available: OK

Redis available via internal API: OK

gitlab-shell self-check successful


Checking GitLab Shell ... Finished


Checking Gitaly ...


Gitaly: ... default ... OK


Checking Gitaly ... Finished


Checking Sidekiq ...


Sidekiq: ... Running? ... yes

Number of Sidekiq processes ... 1


Checking Sidekiq ... Finished


Checking Incoming Email ...


Incoming Email: ... Reply by email is disabled in config/gitlab.yml


Checking Incoming Email ... Finished


Checking LDAP ...


LDAP: ... LDAP is disabled in config/gitlab.yml


Checking LDAP ... Finished


Checking GitLab App ...


Git configured correctly? ... yes

Database config exists? ... yes

All migrations up? ... yes

Database contains orphaned GroupMembers? ... no

GitLab config exists? ... yes

GitLab config up to date? ... yes
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory exists? ... yes
Uploads directory has correct permissions? ... yes
Uploads directory tmp has correct permissions? ... yes
Init script exists? ... yes
Init script up-to-date? ... no
Try fixing it:

Re-download the init script
For more information see:
doc/install/installation.md in section "Install Init Script"
Please fix the error above and rerun the checks.
Projects have namespace: ...
< a few hundred lines of yes>
Redis version >= 2.8.0? ... yes
Ruby version >= 2.5.3 ? ... yes (2.6.3)
Git version >= 2.22.0 ? ... yes (2.24.1)
Git user has default SSH configuration? ... yes

Active users: ... 55

Is authorized keys file accessible? ... yes


Checking GitLab App ... Finished


Checking GitLab subtasks ... Finished


The init script isn't the default one, but every service is running as expected.