Sorry for the delayed response, I’m currently waiting for n8n support to help me identify those workflows. They got erased when I forgot to upgrade my trial.
As soon as they’re able to find them, I’ll paste any relevant info here that I can
To no one’s surprise, I also have this problem with test executions. Pressing on the exact same “run workflow” button on the exact same workflow a second time runs fine.
Workaround:
Download the workflow, create a new blank workflow, then import it into the new one. This fixed the issue for me.