nhhhhs try using the texting support to 611611 and using the automated response to fix messaging (probably wont work).
If that doesn't work the only thing that worked for me (its a real pain in the neck but it worked on two numbers) is porting out the number temporarily to a non Verizon plan such as tello (you will need an extra device to do this) and porting it back.
I think also switching to an AT&T sim from TracFone (you can pick up in many stores for a dollar) and switching your number onto that should work and possibly will also fix the problem even if you afterwards switch back to the Verizon sim. (the TracFone rep may tell you that the classic wont work with the AT&T sim but it does).
The problem has something to do with "baggage" that the phone number has (something to do with being registered to Verizon plus) and porting out cleans it up somehow. I don't understand why or how but I know I wasted many hours on the phone with TracFone and nothing else worked.
