Unable to send text to ONE person

[jtbr]

I am able to send/recieve texts from all but ONE person from my thunderbolt.  When I send a message to this one person I get an error back saying "Unable to send" Both the sender (me) and the reciever have no issue with others sending or recieving messages. 

Any clue?

[Digitos]

Sounds like there's somethingn adding the contact again. Finally, try clearing the unique about this contact. Did you recently add/edit this person in your contact list? Double check to make sure there's not a space at the end of the phone number where it shouldn't be. I've found that my friend phone automatically inserts a space sometimes when I cut & paste or use the auto complete/spell check feature. If that isn't the solution, try removing and re-adding the contact. Finally, try clearing data in Settings/Applications/Phone.

[Digitos]

Hope you can make sense of that, sorry. My cursor jumped on me!