FNB Over pricing the Merchant device called speedee

FNB merchant agreement that I never signed with regards to ****** device. Last week Wednesday the 23th September when we opened the shop we then realize that there has been burglary all stock and some equipments were gone , the Speedpoint was also amongst the ****** things . I immediately alerted FNB Merchant services under technical to stop/block it to avoid any ***** that might take place.I was then told that I will have to pay for the speedee lost and they will charge me as its price . Suprisingly The invoice came today and that smallest device called speedee cost R7000.00.Rediculous I have been renting and over charged which then I am not suppose to pay a cent as its insured on their side ,FNB merchant is overpricing . Yoco for the same device cost R499.00 and Ikhokha for the same device its cost R999.00 Yet FNB charges me R7 139.20. Then can someone please explain to me how much is the big speedpoint surely its R12000.00

I am not gonna relax until this is all sorted , I have all my business accounts , savings so as my personal banking with FNB but this is merely so wrong and cannot accept it .This device is overpriced for no reason.While I am struggling with stock lost and equipmentt here FNB MERCHANT comes and cut even deeper