Refs:merge_requests pipeline rerun with variables

I have a merge request pipeline that failed. I want to retry the pipeline but set some variables. If I try to run the pipeline manually on the branch with variables set, I get an error

The form contains the following error:
Pipeline filtered out by workflow rules.

because the job has

      - merge_requests

Is there a way to “spoof” a merge request event? I’ve tried setting variables

CI_MERGE_REQUEST_EVENT_TYPE=detached (also tried merge_train)

but still get the error.

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