Hello fellow developers,

I hope you're all doing well. I am currently setting up a bot (LLM agent) using WhatsApp API and a Flask application hosted on Azure.

As recommended in Azure's tutorial, I have a startup.txt with the following command

gunicorn --bind=0.0.0.0 --timeout 600 --chdir src/whatsapp_agent/whatsapp_agent run:app

which runs locally without an issue.

Once it is deployed on Azure, however, the webhook setting from WhatsApp API (Edit Whatsapp Business Account subscription) returns the following error:

The URL couldn't be validated. Callback verification failed with the following errors: curl_errno = 28; curl_error = Operation timed out after 6000 milliseconds with 0 bytes received; HTTP Status Code = 200; HTTP Message = Connection established

Did anyone run into a similar issue and managed to solve it?

Many thanks!