Hi @JuliaHe
It's hard for us to troubleshoot this issue for you, especially if you've not been getting any emails from Zapier alerting you to errors?
I'm going to flag this post for the Zapier Community Team. They should have more insight on this and can escalate to the support team if needed.
Sit tight, and someone will contact you soon.
Also, as an aside, check out the "Zapier Manager" integration. There is a trigger that can fire on a zap switching on/off and you could use that to create a zap that alerts you by email or something.
@JuliaHe Hello and thanks for posting on our Community! Happy to help.
To see what the causes of why your Zap stopped, we recommend that you check out your Task History and filter by "Stopped - All" to sort out which Zaps are stopped. Click on any Zap to view the step that contains your error that you need to resolve so that the Zap may get back to zapping. Here's some details: https://zapier.com/help/manage/tasks/view-and-manage-your-task-history
I noticed that one of your Zaps has a missing required field error, here's a guide on how to troubleshoot for that issue: https://zapier.com/help/troubleshoot/errors/fix-required-field-is-empty-errors-in-zap
If you're still having troubles after attempting the above suggestions, please let me now and I will gladly escalate. Thank you!