So you downloaded version FP4.SP21.B.048 from here, right?!
Those are outdated, the current FPOS version is FP4.SP25.B.058, which we don’t have factory images for yet.
For future reference, no matter what people tell you, don’t flash it (if you don’t have a good reason to), that only creates problems, and you loose the ability to restore the stock images through the Magisk app before an OTA update.
That recovery doesn’t seem right, I would expect 12/SKQ1.220201.001/SP25 if you are on the latest release, notice the 12 for Android 12 at the beginning and that bold part at the end FP4.SP25.B.058.
Check your current slot with fastboot getvar current-slot, set it to the other one with fastboot --set-active plus a or b (depending on which one you’re in) and check that recovery version. I think your phone switched slots.
Bootloader is what we want. I assume your phone didn’t boot from the outdated boot.img, right? 
I’ve uploaded you a stock FPOS-B.058-boot.img and a patched FPOS-B.058-magisk-boot.img.
- First make sure you are in the right slot
- Then try booting that stock
boot.img - If that works you can flash it, so we get a blank canvas to start from
- Reboot to see if everything still works
- Boot from the patched image and follow the rest of the installation described above