I installed Ubuntu and had some problems dualbooting with Windows. However, I managed to make it working. Unfortunately, my Windows disappeared from the boot menu (and I cant even see it in the BIOS), tho I still have it installed. I tried using boot-repair but there was an error and it did not help. I found this post https://askubuntu.com/a/890562/1015491 which did bring my windows back, but it says "Unknown command NTLDR". Is there a way to repair this or eventually other possibility of bringing my win back without reinstalling?
EDIT: My boot-repair report - https://justpaste.it/2d9m2 - (activating Separate /boot/efi partition resulted in reinstalling grub, causing again my Ubuntu did not want to boot - I repaired it according to this (https://askubuntu.com/a/1050026/1015491) - but windows was still missing. Windows 10 is installed on sdb3, Ubuntu on sdb5.