Charged for returned phone

After reading several post, I think I’m being scammed like many other Xfinity customers. I’ve been charged $1,050 for a phone that was used 2 days then returned.  I attempted to return the phone before  activating the device and was told I had to activate the device prior to sending it back. I didn’t question this, followed the return procedure and after several weeks Xfinity has charged me for the phone. At a loss and definitely not going to be an Xfinity customer much longer.