Why can't I send texts?

[Android Central Question]

I use a Galaxy S5 and I use the basic Messages app included on the phone for texting. Yesterday I tried sending a response to a text message and it wouldn't send. I tried sending another message to someone else in my contacts and this message didn't send either.

Is there something I can do to correct this? I'm planning on taking a trip in less than a week and it would be great if I can get my text messaging back up and running by then (preferably without having to take it in to my service provider--I'm working most of the days in between and I work 12-hour shifts, giving me little to no time to handle other things on work days).

 

[B. Diddy]

Welcome to Android Central! Any problems with making or receiving phone calls? Who's your carrier, and did you get the phone from them, or was it unlocked from somewhere else?