Tunze Comline 3162 issue

[RickG.]

I have one of these filters on each side of my 75 gallon. Both have decided to not skim from the surface with the lid closed. If I prop it up then it will but not with enough suction to filter. Fully taken apart and cleaned makes no difference. Any help would be of use as Tunze has not responded to my emails

 

[tzabor10]

Pictures are always helpful. Skimmers can be fussy. Especially when cleaned.