I’m unable to answer calls on my Apple Watch series 7

Hi Drrattan

Wondering if not being able to answer calls has just happened after being able to answer them previously.

and

which iOS version is installed on the iPhone 11

You might want to see if anything in these two Apple Support articles helps:

Answer phone calls on Apple Watch – Apple Support

Use Apple Watch with a cellular network – Apple Support

You might want to try restarting your Watch (when not on charger):

Restart your Apple Watch.

and

Also restarting your iPhone: Restart your iPhone.

All the best :-)

What happens when you try to answer? Are you seeing the call show up on the screen? Answer phone calls on Apple Watch - Apple Support