Husqvarna wheel keeps falling off

I have a husqvarna LGT2554 that am having problems with one of the front wheels, right, keeps popping the "C" clip off which then makes the wheel to fall off. I have bought 5 new "c" clips and they do the same. The washers are there and i believe in correct placement. Thought the new clips were wrong and even got one that had to hammer it on to make sure it was tight but still popped off.



Please Help!