Is your horse nips when you do up the girth

My horse started  nip me when ever I did up the girth. So to fix that I put on the girth on hole one then I took him into the arena. I did one lap then did up ONE side. And then I walked him around one lap again and did up the other side. I keep doing that until his girth up up all the way and got on. After that for a few weeks he stop moping me and I stop doing the girth exicersize. He never nip me and my sister when ever I did the girth up again.