Time falls increasingly behind, occasional BSOD, now laptop not turning on at all

The problem started about a month ago, I came back home from holiday after a week, the laptop lid was closed and laptop was in hibernate mode and on battery power. Turned on the laptop and battery went from ~90% to 0% within a couple minutes, plugged in and everything was fine. Couple days later time starts going behind, up to over an hour behind throughout the day, also occasionally get BSOD after waking from sleep. After getting this for a few day figured the time and BSOD were related, and after doing all the software fixes known on the internet gave up for a few days. Problem still persists, replaced the CMOS battery, this didn’t do anything apart from booting slightly faster. After a week of getting the same problem I figured it might be a problem with the battery but didn’t want to buy a new battery until I tried everything so I reinstalled windows 11 (without formatting disk, not sure if this is relevant). Issue was still there, used task scheduler to launch /wtm32sync every 15 minutes, clock was still behind after waking from sleep, but I gave up on trying to fix it and wasn’t too noticeable because it would sync after every 15 minutes. Occasionally would wake from sleep mode and the screen didn’t turn on, turning off and on using the power button would fix it. I got the same issue at time of writing (09:41 22/10/2023). Turning off and on using power button (power LED is on) and screen still not turning on. Plugged in to power (charging LED is on) and screen still not turning on. After half an hour of charging screen still doesn’t turn on.

Okay you have told us what happened but what is your question? I suspect you are asking what should you do next? Due to the number of possible failure reasons I would take it to your local repair shop where they can carry out diagnostics.

More details about the device and full OS details would also help.

I don't know how old your laptop is but it sound like it may be dying. I don't think this will work but you could try reseating the drive and memory modules.

You said your reinstalled Windows 11. Since you just did that I would start again.
Remove or unplug the laptop battery. Run the computer only on the Power Adapter as a test.
If you have a Windows 11 USB Flash Drive installer, boot off of that and do a Clean Install.
Choose your Language, the Install Now, then Custom Install.
In Where Would You Like to Install Windows? Delete ALL partitions so the whole drive is Unallocated Space
Press Next, Windows will create partitions and format them during the install.
If you still have issues, the laptop has some other hardware issue.
As stated if it is an older laptop, it may not be worth pursuing this any further.