can´t use the pencil corectly

I was drawing on my ipad and had no problem with it when suddenly the pencil tool stoped working (or technically it still works but its really transparent). I havent changed the opacity and it layer setting is sett at "normal". I havent changes pensil from the standad one and I even tried to change hardness but it didn´t make any diffrent. When I use the bucket however then the colur become exacly how it supose to look.

What is the prombem? and how am I gonna fix this?