at&t cellular 982.00 bill for rist 15 days of service Internet

i have been a long time customer with us cellular i decided i would switch to att thinking i would get a better deal i talked to the  saleswoman on the phone to finish switching phone service to att the woman assured me there would be no deposit required for three line family plan. i specifically told here if there was i did not want to switch to there servie  i received a pro rated bill for 382.00 dolles in the first 15 days i payed it on time the next week they sent me a bill for 982.00 for deposit on three phones they said my credit needed a deposit after they told me there wasnt no deposit.so i switched back to us cellular with no deposit but now it seems att is going to bill me 350.00 dollars for each phone for breaking my contract when they lied from the very beginning if they wanted a deposit they should got it when i payed for the activation on the phones never did buisness with a more sorrier outfit ever please be aware im sure i aint the only one this is happend to but im back with us cellular 11 yrs  i should of never left