QUOTE WRONGLY GIVEN

on 4th august 2020 i phoned the courier guy klerksdorp for a quote on around 10kg parcel to be delivered in thabazimbi. The lady said the overnight is R680.00 and eco roadfreight R 207.00. This is the prices given to the client.. Well the contents alone weight 13kg, The courier Guy sent me an invoice for R 2 883.00. when i contacted them they said the following: "Die fisiese gewig was 17 kg maar omdat dit na ‘n antionale area toe is werk ons op die volume massa wat dan 49.06 kg was. Wees ASB bewus dat ons op nationale areas werk op die grootter kg tussen fisies & volume gebruik dus ASB ECO. Hoop u vind als is in orde " I have photos of the contents on a scale the total of the contents alone was 13.84kg. now we wont have a problem paying in that difference.. But to send us an invoice for R 2 883.00is ridiculious. When the quote was given no one said anything about working on bigger scales as the lady stated in her email.. I have email photos four times already.. and my supplier where parcel was collected also stated that the boks did not weigh 17kg. I want this problem sorted out asap.. The quote was given wrongly by the courier guy staff and I just get any feedback from head office as well. Now the boss want me to pay this difference in.. i feel it is unfair beacuse the problem was at the courier guy staff member who never stated that kg will be more ect.. please help me sort this out,, i dont have money to pay in for someone else's fault.