Phone crashes

[Graceunlimited]

My Samsung s24 ultra keeps crashing out. Several times and my phone is up to date. 

What should I do? 

[Mujibar]

Can you describe what is happening in a little more detail? "Crashing out" doesn't tell us much.

[Graceunlimited]

It just crash and turns off and on. Then stable for some hours and crash again

[nullandvoid]

So, it's restarting on its own?  You get no warning, like an overheating warning?  Have you tried clearing the phone's cache partition?  If you boot it into safe mode, you will be able to tell if some third party app is causing the issue.  In Safe mode, only Samsung apps run.