Active Leveling Failed - Problem with lift?

[bwpowell 0]

After a failed print where the model came out string-y, I was able to cancel the print and clean the mess it had left behind. I cleaned everything visible which had fallen off the build plate, and proceeded to begin printing another different model. The bed seemed to be calibrating correctly, nothing off, yet it would lower itself and then raise itself halfway multiple times during this process, until it finally lowered itself completely and claimed error 22 (failed leveling). There is nothing under or around the build plate, and there is a slight rattling in the back where it lifts. Is it possible a piece of filament is the issue and is irritating the lifting mechanisms in the back? If so, how can I clear it out? (Compressed air unfortunately doesn't seem to be working)