Bf Measuring help plz

Tribesmama

I bought a set of calipers to help measure my BF% .
It says to pinch an inch above the hip, measure 3 times and take the average.
Well mine is 6mm and on the chart it means iv got 16% bf. Which if you look at my profile pic im nowhere near that thin.
Any advice on getting an accurate reading with the calipers much appreciated