I had a subclass that I created and it was published. I decided to create a new version of it and the only thing I added new was an additional feature to level 3. I made sure that it is set at level 3 and saved. I also edited some wording on the other features but haven't touched the level. Now every time I try to publish it, it keeps giving me the error "This homebrew Subclass does not have the necessary class features with the correct required levels." I'm not sure what I'm doing wrong.

Is it a fighter? There is a glitch currently that requires an unnecessary 5th level feature. Keep playtesting and editing and sooner or later the bug will be fixed and you will be able to republish it normally.

In case you're encountering the same issue that I had recently; the system only checks your classes, races etc. when you save them from the main edit page (i.e- the button beneath the basic/additional information). Saving changes to individual features etc. doesn't trigger the check. I've also encountered a few cases where I'm given an error that isn't correct, i.e- complaining my content is too similar to something else when actually the issue was that I'd checked sub-races but hadn't added any.