I've getting a FR2846 error for a week. Help!!

I’ve been receiving this error for a week now..

FB2846

The filament buffer signal is abnormal, the buffer may be stuck or the filament may be tangled.

Nothing I do will clear it. I’ve followed the WiKi and tried everything I can think of but nothing will clear it. Printer works ok with the external spool but not with the CFS. I think the buffer is failing.

Any help would be appreciated.