Error code: 0700 8004 180905 - Failed to pull back filamet

Hi to everyone,
i have some problems with the AMS, I hope someone could help me.

I had some filament stuck in A1 slot of AMS, in the PTFE tube under the AMS, I had to dismount the AMS to unstuck, while I’m pulling out the filament form the other slot something gone wrong with the slot A4, after the filament come out the led became red (not blinking).

I’ve correctly removed the problem in A1, mounted back and at rebook the slot A4 have the red led, no filament stuck. maybe a little pieces of filament is stuck in the first ams hub 4 to 1?

The error message is:
AMS failed to pull back filament.
This could be due to a stuck spool or the end of the filament being stuck in the path.
0700 8004 180905

Somone could please help me?
Thanks