Question PC does not turn on until and unless I hold the power button for 10 to 20 seconds

[LOSTSOUL7]

So, I have a 1year old setup and for around the last 2 to 3 weeks my pc does not turn on unless i hold down the power button. After turning on everything runs perfectly fine, there is no issue whatsoever, but it is only during the power up time.

I just want to know if it is really the problem of my psu and if not how to check for other ways and if yes then what should i do with my psu

Components:
Ryzen 5 5600g
Mobo: MSI B550 pro vdh wifi
No GPU
G Skill Trident z RGB 16GB 3200mhz ram
PSU: MSI Mag 650w
Case: Ant esports 511mt

 

[COLGeek]

Does your case have a both a power and a reset button? If so, reverse them where attached to the motherboard front panel connectors, making the reset button the now power button.

Press as normal and see if the system starts properly.

Intent is to rule out the current power button as the problem.