Help! My Vertex Skimmer is actin crazy!

[Timbits]

Hi guys i really need your help, i have a Vertex IN-250 and lately its been acting crazy! Basically, its not skimming and fills the cup too fast. I tried adjusting the air intake and lowering the water level and it seems to help a bit but now i have it on almost open and the water level is like half of the suggested operating level.

I don't know what to do and it's driving me crazy!

Please help!