USB-C not working after upgrading to Monterey

Welcome to the Apple Support Communities.

First, try these steps:

• Disconnect and reconnect the external devices to your Mac.
• Connect your external device to a different port on your Mac.
• Test the connection using different adapters.

Then, reset the SMC: How to reset the SMC of your Mac - Apple Support. Test your accessories again.

If the issue persists, Use Apple Diagnostics to test your Mac - Apple Support to see if anything is flagged. If something is, or they still won't function properly, contact Apple Support: Get Support.

Jack

Some ThunderBolt devices on the M1 MacBooks of all descriptions are having problems doing more than one thing at a time. Apple is not using the Intel ThunderBolt controllers. In my opinion, are having complexity issues because they have to do so much more at once in their own software.

You can buy a USB-C to USB adapter for about five bucks on Amazon, to get your other peripherals off the Apple Multiport adapter AV HDMI port. That might make 'most everything straighten up and fly right.

an experiment would be to disconnect everything except the HDMI, and fiddle with it to see whether you can get the screen to light up by itself.

WHAT make & model USB-C hub are you using?

Same issue!

My second screen stopped working (I have less screen space to work on)

My Network USB-dongle stopped working (I now cannot connect to my internet router directly for faster speed)

My network printer does not come online while connecting to my router or directly to the laptop(I cannot print).

What I've tried:

Resetting CMS - did not help.

Apple Diagnostics - did not find any issues.

Trying different ports - did not help.

Trying different dongles and USBc adapters - did not help.

Restarting all devices while connected or disconnected - did not help.

None of the above worked.

I'm so angry and frustrated.

I might roll back to the previous OS because Apple you have messed up my work setup.