Text message blocked
I don’t block any messages. Yet, I am unable to send to a couple of numbers and they are unable to text me. None of us has blocked messages that we know of.
Use Messages with your iPhone, iPad, or iPod touch - Apple Support
If you can't send or receive messages on your iPhone, iPad, or iPod touch - Apple Support
if the link provided doesn't help, then contact your cell phone provider to resolve the issue as SMS is a carrier feature.