Glitch URL not working in WhatsApp Webhook?

We are adding a glitch project URL in WhatsApp webhook but from yesterday we have been getting errors (The callback URL or verify token couldn’t be validated. Please verify the provided information or try again later.)
We already checked everything and got this (

don’t know how to solve this. also don’t know where to find the right solution on Facebook or on Glitch. (Following facebook docs for whatsapp webhook setup)