hotpoint F05 error?

I had an F05 error on my hotpoint machine. Turned off at the mains, removed filter and various items blocked. As i was removing the blocked items the bit that turns on the filter snapped and had to get a new one (exactly the same). Now i put the filter in and doesn't screw all the way in, needs one more turn to complete. Turned it on and water comes out. Any ideas? why does the machine filter kit have 3 bits?

julian
May 2014