Nutesquirrel

I bought headbutt for $2000 and tought it to my Sentret and it dosent show the move when I went to use headbutt on a tree it said I this pokemon don't know headbutt and now I'm $2000 short and my Sentret don't have headbutt as a move I don't know how it happened so I really cant explain any better then this.

I bought headbutt for 2000gold that I tought my sentret and now it don't show it as a move that I tought it and now I'm out on 2000gold