My AT&T HTC Tilt won't let me text?

[shaner]

I've got the first HTC Tilt from AT&T (it's not the newer HTC Tilt 2, it's the black model that I got probably three or four years ago?). All of a sudden my phone has not been very cooperative with me. It won't let me text, or do anything that needs the function of the keyboard. It'll let me type out the name and number of the sender, and when I move on to the body of the text I'll be able to type out a few words then the keyboard will stop functioning. The phone then starts lagging intensely, I can't even send the portion of the text I've already typed and I'll need to do a soft reset. It's the same with any type of keyboard I use if I try to use the on screen keyboard, in portrait or landscape screen. It's not only text, but the same happens if Mobile Office Word, and basically whatever needs to have something typed out. I have not tried a master reset yet, because I'm hoping someone may have a solution in which I do not need to reset all my settings. I do have certain non-AT&T supported programs installed on the phone such as S2U2 and such, however it has never been an issue for me, unless it's suddenly decided to mess up my phone. I've deleted all messages and pictures, currently I'm using 45mb of storage space, with 80mb free. I've tried going to AT&T stores seeking help, but they all tell me they unsure with my programs and just tell me to do a master reset. So, please please let me know if anyone has any suggestions!