dc freezes on date/time screen help

[sdrtodd]

the problem is clear the dc stays on the date/time setup screen and won't boot up any games.

the reasion that im asking for help is that it might be something like an internal battery that need replacing or some kind of system reset that i dont know about that doesn't warrent going to a repair shop
if it can be fixed by myself if not ill buy a new one as i think it will be cheaper then a repair.

as far as i know it might of been a common problem

so thank you for the amazing help that you have given me
im so sorry that ive wasted your time.