Message Not Delivered still a problem for certain contacts

Hey there, Bob!

Thanks for visiting the Apple Support Communities to get help with messaging on your iPad. You've come to the right place!

First, make sure you've gone through the steps outlined in the Apple Support article If you can't send or receive messages on your iPhone, iPad, or iPod touch - Apple Support.

It looks like this is not happening with all your contacts. If the contacts you are having trouble with appear to be non-Apple users, we'd next suggest making sure you have SMS Forwarding enabled: How to forward SMS/MMS text messages from your iPhone to your iPad, iPod touch or Mac - Apple Support. This Continuity feature allows you to send and receive SMS text messages on your iPad, using your iPhone number.

Get more information on what you can do with Continuity here: Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support.

Best!

Thanks so much for following up, Bob!

If you're still unable to send messages from your iPad, the next step is to get in touch with Apple Support directly for additional assistance. You can do that here: Get Support.

Cheers!