Bad practice from technicians

I recently had trouble connecting my cell phone to the Wi-Fi from a new gateway I just installed. I called the Xfinity customer service number and the technician worked with me for almost an hour, before he determined that my phone was bad & he was sending me a replacement at no cost to me. I asked several times telling him I did not want to pay for it. He told me no, but there was a one time charge of $19.50 & I agreed. Got the phone & tried to get it activated, when I was told the technician gave me an offer for new customers only & I sent the phone back. As soon as I returned home, that technician called wanting to know why I was sending it back & after long discussion, he determined that it was a miscommunication & the technicians at the Xfinity store were lower grade & did not know what he was doing, so he sent me another new phone & told me to wait to activate it until he call me.
When he called, he put me through to another technician to activate the phone & both reassured me that the phone would cost nothing to me. I had internet problems so a third technician talked to me & fixed the internet connection to my phone, & then put me in touch with yet a fourth technician who had no clue what was going on with me. When I explained it to him, he told me he needed to contact the fraud department.
I understand they are telling me the technician should not have done that, & did it twice, both times the technician told me he got permission from his supervisor to do this. I know they can trace who it was I talked to from the order he sent me, so it is fraud within their own customer service. It seems to me like they want you to believe it was free just so you will be charged for it later. I was so upset after talking to a supervisor that I threatened to leave their service altogether.