I can’t get my mic to work on my Apple Watch. I have the first series. How do I get mic to come on? I can hear call but they can’t hear me and no mic Irvin is displayed at top of watch face. Is there a fox?

First force restart it

i.e. press and hold both the side button and Digital Crown for at least 10 seconds, then release both buttons when you see the Apple logo.

Then Force Restart the paired iphone   Force restart iPhone – Apple Support

If that is no help

 Unpair and erase your Apple Watch

and then

Set up your Apple Watch

 If no better you may want to unpair then set up without restoring the backup.

You may also want to make sure the software on the watch is up to date.

Update your Apple Watch

If you've completed that troubleshooting and the issue is still not resolved, Contact Support.

Click here > Contact - Official Apple Support

or phone numbers 

Click here > Contact Apple for support and service - Apple Support