Now cell phones

I purchased Now cell phones on December 2nd the phones came they were cheap phones immediately sent them back The phones would have been returned by the 10th yet Xfinity now took $50 out on the 2nd for the shipping of the phones then took $ 37.34 twice on the 18th to pay the monthly bill for the phones that I'd already sent back that they already had back in stock now they won't give me my money back they claim they already did My bank says they're a liar can't get a hold of anybody to help with this situation I've spent hours on the phone