It is just as the title says, for some reason those 3 buttons (up, right, and down arrow) won't work. I've tried restarting by pressing the little button in the back, and also tried taking out the battery and putting it back but neither worked. None of the keys are sticky either. Any advice would be appreciated, thank you!

what happened? What did you do before it didn't work anymore?

I once dropped my nspire on the ground, and the arrow square touchpad thing stopped working, but I was able to fix it by removing the battery. Did you drop yours?

If it's less than a year old then just return it for a new one.

The first thing to try is disassembling the calculator and wiping off the circuit board with isopropyl alcohol. Also, inspect the rubber key membrane for any damage. I'm skeptical that will resolve the issue but it's the only easy option.

The second thing would be to use a multi meter to figure out where along the circuit board a trace broke. Once you find the area, you'll need to solder a wire to bridge that gap. Do you have any experience with these tools?