Why can't I capitalize letters using my keyboard?

Okay so I have an RCA tablet, 10 in. Viking Pro, and I've had a minor situation with the keyboard. When I use it it won't let me capitalize letters. I shot RCA an email and I just got a replacement tablet. But guess what? Still doesn't let's me capitalize letters. So, the problem is obviously with the tablet. I REALLY don't want to send the tablet in because I've already put so much on it already. I need a way to fix this without getting a new tablet. I've also reset it a bunch of times, didn't work.