Why was Bitlocker Recovery triggered on new working Ideapad laptop?

Starting today, my Ideapad 5 laptop that I bought in May and have been taking care of, only shows the Bitlocker Recovery screen upon boot, preventing me from proceeding into Windows. I do not know my Bitlocker key - however, this was not a problem before, and I am not sure what exactly changed in the boot process to prompt Bitlocker recovery to activate. The backstory: I bought the laptop earlier this year. Upon setting it up, I was unpleasantly surprised by the need for a compulsory Microsoft account to activate Windows 11, and instead used a workaround to create a simple Username + Password

Question by Rashid on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.