Missing previous comments when diffing against new commit

Summary

Comments from a previous commit are not visible when diffing with a new commit

Steps to reproduce

1. Create a new merge request.
2. Comment on specific lines of the code diff. Comments appear inline with lines of code.
3. Add a commit to the merge request.
4. View the diff between commit 1 and commit 2. Comments for commit 1 do not appear inline with the lines of code.

Example Project

Comments on commit 1 https://gitlab.com/j-joshua/jjtestproject/merge_requests/1/diffs?commit_id=e9a4b200a57d134da05060a837edf6fe29f986ed

Comments missing when diffing commit 2 and commit 1 https://gitlab.com/j-joshua/jjtestproject/merge_requests/1/diffs?commit_id=56b9e345bc2561cccb5c76cfcd6584175925ec50

What is the current bug behavior?

The diff between commit 1 and commit 2 is displayed without comments inline for commit 1.

What is the expected correct behavior?

Comments appear inline for commit 1.

Relevant logs and/or screenshots

Output of checks

Results of GitLab environment info

Results of GitLab application Check

Possible fixes