I was using the webhooks to check if a client rejected the phone call. I was using the end-of-call-report webhook, but I noticed it is no longer being fired whenn the client rejects. What other alternative do I have via webhook to check if a client rejected the call?

If you are not receiving the end-of-call report for calls that do not start, use GET on the call endpoint /call/:id. Additionally you can use a cron job to poll the endpoint.