how can tmobile open an account for me without my knowledge?

I just switched to tmobile after being with Verizon for 14 years. I'm shocked that the customer service agent that I talked to about plans actually opened an account for me during the call. I hadn't decided to join yet. When I finally did decide to go with tmobile and went to a local store, they said an account had already been opened for me 3 weeks earlier. The problem with that is, I didn't have time to get my payoff statement from Verizon before the keep & switch expired. Also the person at the store copied down my payoff amounts for all 4 devices before I canceled my Verizon service, bur apparently that does not satisfy the payoff statement requirement for keep&switch. So when I then canceled Verizon I couldn't access my payoff anymore and had to order it to be mailed. Tmobile really messed me up. I'm already ready to leave tmoble and I just got here. Wish yall were more organized/better at customer service. Verizon has outstanding service all around. I only switch bc I thought I could save. WRONG.

P.s. your sub forum dropdown slider doesn't work on android in chrome.