iOS16 not sending group text messages with Adroid users

Help, please -

I recently updated to IOS16. Prior to the update, I had no problem with group text messaging involving any Android user. Now, I can send a single text to an Android user, just not any group text messages. I receive a "Message Send Failure". I have tried every recommended fix out there, checked the SMS and MMS settings, reset to factory settings, on/off, etc. to no avail. Is there a fix for this issue?

BTW - I contacted Apple support and they suggested it was a hardware issue. I find this hard to believe since I did not have any issues prior to updating to iOS16. My phone has been operating fine, too.

Many thanks for any help you can provide.