You should simply follow the classic steps of installing an hotfix:
- (Turn on Airplane mode THEN de-activate OTA blocker. Leave airplane mode on for the
remainder of the operation)
- (Restart kindle (not a factory reset, just press the power button for some time), though
I'm not sure if that's necessary)
- Download the 2.2.1 hotfix
(
https://github.com/KindleModding/Hot...ses/tag/v2.2.1) and copy it to the root
of your kindle
- eject & unplug kindle
- On your kindle, go to Settings->click the 3 dots at the top right corner->update your
kindle
- Run hotfix (click on the run hotfix book, search it in the search bar ("Run Hotfix") if you don't see it)
- Re-activate OTA blocker (and only once it is done running may you re-activate airplane
mode)
I have myself successfully done this operation on a kindle PW 12th gen, and suddenly all books (and .sh) I had downloaded appeared in my library (because these didn't show otherwise)
Hope that helps.