Pc startup problem

New pc

9800x3d

X870 aorus elite

5070ti

Psu fsp vita 850gm

It was working perfectly but suddenly when i press the power button the pc don't start up but the case fans initiate a spin then stop and the fans rgb also flashes

A second longer press its like a fraction of a second longer the pc works fine no problem

Also if i put the pc to sleep when i try to wake it up it shut down

No motherboard erorr nothing and its stable under load and gaming