Webhook Error: HTTP Error 400: Bad URL request
Issue
A webhook that looks to be structured the same as other functioning webhooks is failing with HTTP Error 400: Bad URL request.
Solution
A 400 error message usually means that the request was malformed. In other words, the data stream sent by the client to the server wasn't formatted in the exact way required by the receiving service. You will need to work with the service you are trying to reach to figure out the exact cause of the error with the webhook.