Pull request not merged

[rtc11]

How would you describe the issue?

Auto merge me from a workflow_run reports success with a generic error message.

How can we reproduce the issue?
On a public repository, use this exact setup:

Follow this guide: https://stefanzweifel.io/posts/2021/04/28/auto-merge-dependabot-pull-requests

Comment the pull request with @dependabot rebase to trigger the workflow where github..actor = dependabot[bot]

What are the expected results?
The pull request was merged

What are the actual results?
The action reports success ✅ , the pull-request was not merged, but this message is logged to the action console:

An error occurred while merging the Pull Request. This is usually caused by the base branch being out of sync with the target branch. In this case, the base branch must be rebased. Some tools, such as Dependabot, do that automatically.

How much does it hurt?
The action does not seem to work.

[developher-net]

This is driving me bonkers. Because dependabot runs on a schedule, multiple pull requests are created simultaneously and only the first one to complete gets automerged by merge-me-action

If you tell dependabot to rebase a PR, it does so successfully, but merge-me-action still reports the branch as out of sync. I can manually run the merge-me-action action again, which successfully merges, but that defeats the entire purpose.

[zaneselvans]

I'm also experiencing this behavior, e.g. on this workflow run. I had some successful automerges when I was setting things up initially, but now it seems to always fail in this same way.

[fizyk]

Happens for me on a single repository actually https://github.com/fizyk/pyramid_fullauth/actions/runs/3760533656/jobs/6391347098 other repositories with same settings are fine. And even if I ask dependabot to rebase or recreate the outcome is the same.... 😕