Being overcharged on the same product in FBA fees, no change to packaging

I downloaded my transaction data for one of my ASINs and I've realised that across the 12 months, there have been hundreds of orders that have been overcharged a fee more than what I was expecting to pay. There has been no change in packaging, and it's possibly also been from the same stock.

I had this issue a couple of years ago and lost about £600 in overcharged FBA fees for ONE ASIN that I calculated. I was being fobbed off by SS under the pretence the fees had changed, but this was pre-fee update.

I've now realised the same thing is happening again and I don't think most sellers are aware that the fees for the same product/dimensions are fluctuating.

Has anyone else notice this? I assume most sellers may not monitor this.