One Max on AT&T GoSMS not working topic

I used to have a Droid DNA that I used on AT&T with no problem. I just used GoSMS Pro for my mms. Now, on my One Max, I can't send or receive mms with GoSMS or any other app. I looked through the threads on here and searched Google but I've had no luck finding a fix. Any help would be great. I love this phone and don't want to have to give it up.
Thanks