Ebay Newbie.. Help ME!!PLEASE!!?

[Ebay Lady]

Ebay Newbie .. Help me !! i am a new seller on ebay and listed a new schwinn cs bicycle for 200 or best offer before i listed my item i used the ebay shipping calculator to sample rates and it gave me a rate of $54.00 dollars for UPS ground so since i thought the shipping was a good price i decided to offer free shipping a seller made me an offer and i sold my item i went to PAYPAL to print label and it was givng me an amount of $84.00 dollars i used the same dimensions and same package size i even went back to the shipping calculator using the buyers zip code and i got the same $54.00 tried printing the label on paypal and it says $84.00 i contacted ebay and the customer service rep said since i offered free shipping i wont be able to get the discount and will have to pay the retail price of $84.00 and he said PLEASE DONT OFFER ANYMORE FREE SHIPPING. lol i had no idea can someone help me im just confused....This are the dimensions of the package is my own package 53LX8WX28H my zip code 90011 other persons zip code 44622
Thanks for the advice i will be using fed ex which came to $ 61.00 dollars but i dont know if that is against ebay rules i contacted the buyer and he was fine with it. I changed the shipping option on my other bicycle to local pick up LOL no more free shipping hopefully this other bicycle sells as fast as the first one did wish me luck!!