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Error 400: MISSING_SUBJECT (Please include a subject line)

Hey! I am setting up a Stripe webhook.

I made a new API workflow and when setting it up used ‘Detect request data’ and used the /initialize url to test the webhook. Then I remove /initialize from the url so that stripe sends the normal requests to the right url. When I send a test request then I get this message:

I am puzzled because I cannot find any information about this error on the forum or the support pages of Bubble.

This is what the API workflow looks like:

Okay so I went to have dinner and didn’t change anything and now it seems to work fine. How is this possible?

I had the same error. In my case, the problem was that the Webhook trigerred a “Send email” action in the workflow. In this action, the Subject field was empty. Everything worked once i added the subject.

Wow, what a shocker that one could address an error message that says “HEY YOU NEED TO INCLUDE A SUBJECT LINE!” by adding a freakin’ subject line. Floored.


Hahaha. That is one of the clearest error messages I’ve seen.