I would strongly advise you to get a quality psu it may or may not be the source of your current problem but a quality build needs quality components.
Corsair rm Phanteks amp to name a few.
That's the plan so far when I can I'll get a quality psu and calling an electrician as soon as possible I feel like it's one of the two.
This. The PC in question is a prebuilt system, the crap they'll have put on there will be astonishing. Do a clean install of Windows (not a reset). Obviously either back-up the OS or ensure you have the original image usb/cd/partition still secure first.
I've clean installed via usb using media creation tool (tried regular reset at first) and installed nothing but AMD GPU driver and AMD chipset installs I'll just list the things I've tried with help from the people over at techpowerup forums.
Disabled PBO (builders enabled when I had stock cooler on)
Updated all drivers via AMD Auto detect
Made sure Ryzen Master was running on the default OC mode
Updated bios
Disabled XMP (and setting different memory times)
Increased DRAM voltage
Disabling Radeon Software Auto OC tuner
Disabled/Enabled Freesync
Disabled/Enabled Vsync
Disabled Enhanced Sync
Increased memory clock
Decreased core clock
Cleaning old drivers with the AMD cleanup utility
Disabled PCIE power saving
Disabled 10-bit pixel format
Disabled Microsoft game bar
Disabled discord overlay
Set audio channel to "stereo"
Increased the card's power limit via MSI Afterburner
Updated Ryzen Master
Set refresh rate to 60hz (from 144)
Set games to run at 1080p
Ran memtest for 3 hours, 3/4 passes with no errors
Ran crystaldisk, ssd came up as healthy
Reseated GPU
Reseated RAM
After all that is when I clean installed with the usb (Sorry for the long message just wanted to list what has been tested).