Help with understanding seller fees please

I sell accessories for tools so my seller fees for these products should be 13.26% as they fall into the category DIY & Tools but some of my sales are being charged a sellers fee at the standard rate of 15.3%. Can anyone explain why this is happening and what I can do to rectify it?
I have checked the Browse Nodes and they seem to be set correctly.
Examples
Order ID: # 203-1658619-6272327, ASIN: B09ZJ7ZLC4 - charged a fee of 15.3%
Order ID: # 026-9689063-6257940, ASIN: B09MSTK7RT - charged a fee of 15.3%
Order ID: # 204-8089651-8672329, ASIN: B09Z34NG2B - charged a fee of 15.3%
Order ID: # 203-6348328-3721156, ASIN: B01E1BN1J0 - charged a fee of 13.26%
Order ID: # 206-7094864-8584358, ASIN: B06Y33GF46 - charged a fee of 13.26%
Order ID: # 202-0924520-8110758, ASIN: B09ZJ64XB7 - charged a fee of 15.3%
Order ID: # 204-3346638-6759558, ASIN: B01KVLYZIU - charged a fee of 13.26%