I'v been using a dual boot system with Windows 10 and Ubuntu 18.04 on my desktop for almost a year. It however stopped working recently. The GRUB menu appears at start as usual but when I select windows, it simply resets the GRUB menu without showing any error. I can still login to Ubuntu without problem. I tried booting to windows directly through the motherboard interface but it just leads me to the GRUB menu.
I followed the suggestion here on trying the boot-repair several times with no help. My boot info summary is here http://paste.ubuntu.com/p/3vrb9cpTvR/
I thought the disk might be corrupted so I tried ntfsfix as suggested in Fix corrupt NTFS partition without Windows but it did not resolve the problem. (It did break my nvidia driver on Ubuntu though, not sure why)
I then tried starting with my windows install usb and tried to recover by restoring a previous restore point. The restoring succeeded according to the software but the GRUB menu behavior remains the same. I also tried window's startup repair and it claims it repaired it successfully but the GRUB menu problem remains.
I tried boot-repair again after restoring windows but nothing have changed.
My OS are all installed on a NVMe ssd, I believe the MBR is at /dev/nvme0n1p2 and windows is at /dev/nvme0n1p4. /dev/nvme0n1p1 is windows recovery environment.
I have been aware of the common dual boot problems such as windows fast startup and have disabled it. At this point I have no idea whats the problem and not sure what to check next.
Please help me diagnose this problem. Suggestions are appreciated.