Galaxy S4 will let me receive MMS texts but I can't send a text to anyone!! HELP

[Traci Stiltner]

I can receive texts n pics and I can send pics but I can't send a text it says failed!! Called ST n reset APN several times still not working. PLEASE HELP?!!

 

[stalemate1]

I can receive texts n pics and I can send pics but I can't send a text it says failed!! Called ST n reset APN several times still not working. PLEASE HELP�!!

Can I recommend whats app or viber?