Trying to cancel phone service. Suspicious questions

I called to get my Xfinity Voice removed from my services. The technician said he could reduce my bill to $103.43 and get me a free iPad, after paying a tax of $49.99. I asked how much would it be if he lowered my speed to 800 mbps (from 1000 mbps). He came back and said he got me another deal where I could keep the 1000 mbps, get the free iPad, and only pay $83.40 per month. I thought this was OK. He asked for my Social Security number and date of birth. I felt a little funny giving him this, but I went ahead. He then said that my credit check was locked (which it was), I told him I would unfreeze it if he told me the credit service they are using. He said I wouldn't have to do this if I gave him the social security number of a family member. Alarm bells went off, and I told him there was no way I'm giving him that info. He said OK, they're using Equifax. I unfroze the credit check, and he was able to get in and verify my credit. Then he wanted me to pay the $49.99 tax fee (I assume for the retail price of the iPad?) by using a credit card. I asked him to have Xfinity add it to my bill, and he said he could not do that. I kinda freaked out and told him to forget the whole thing, then hung up. Is this normal? Why would he ask for a family member's ss number, and why can't Xfinity bill me for the iPad tax?