None of the access tokens I'm generating and testing are working from my account. A colleague is using the same script and his runs fine and his access tokens are validated but when we use my access tokens I get back a "Request failed due to: 400 Client Error: Bad Request for url: https://graph.facebook.com/v20.0/387080054495014/messages " error message.

I've tried doing a ton of things from the Business Manager settings by adding developers and creating a permanent access token with all the permissions and I'm still getting the same error.

Is there another issue with my account that I'm not seeing that is preventing me from sending messages through the API with the access tokens (both temporary and permanent) I've tried to use? The strange thing is that yesterday it started working for an hour and then it stopped working again. Please help!!