iphone 13 immediately shows 'call failed' when trying to make a call

Welcome Shaboom6,

Thank you for using Apple Support Communities. Based on your post, your iPhone 13 shows 'Call Failed' immediately after attempting to make a call. We'll do our best to assist with this.

First, we'd confirm you've tried all steps in: If you can't make or receive calls on your iPhone

Then we'd change your environment and try making a call again. Sometimes there are surrounding obstacles that interfere with cellular signal.

Try making a call during another time of day, due to network performance issues.

If the issue persist, make sure you've contacted your wireless carrier for next steps: Wireless carrier support and features for iPhone in the United States and Canada (Select a different region at the top for their wireless carrier options.)

In case it continues and no issues on the carrier's end, then please reply back letting us know if this happens with multiple contacts. Does it ever make the call then connect or fail each time?

Wishing you well, take care.