Ending Calls made by callin.io

Hi, I've set up an automation using callin.io that's triggered by a Fillout Form. This automation then prompts callin.io to initiate a voice call to the contact. My callin.io account is connected to Twilio. The issue I'm facing is that the call doesn't terminate unless the customer hangs up. This has resulted in calls continuing after the conversation has concluded, which has rapidly consumed my Twilio credits. How can I ensure the calls end properly?

I would greatly appreciate any insights!