What is binding now because this is not stated in the price quote, even though I have filled in all the details

Questioner

Via Marktplaats I found an interested buyer for my fishing gear without shipping costs €400, now I want to send it and via TNT express this was possible and via the site the shipping costs came to the quote of €77. The buyer agreed to this and I requested the shipping and made the choice of sender paid and this amount in consultation with the buyer increased in the purchase price and this also went correctly, but after creating the shipment I did not receive an e-mail confirmation about this from TNT and also called how I should pay the amount. When I received the invoice by post, the costs for shipping turned out to be €154.47 and I asked for an explanation about this. =, according to them it was an exceptional size and according to a formula calculation this was the amount to be paid. My question is what is now binding because this is not stated in the quote while I have filled in all the details 198cm*45*20 and 13 kg.

Lawyer

That additional story about extraordinary sizes should have been made known to you in advance in special conditions, you could also have been warned. The question is whether it makes sense to make a legal procedure for the difference.