Fake and deceptive t mobile promotion

Also deceived by the T-Mobile in Manor tx.  The worst store ever!! I was told I could add a line “free”.  I asked multiple times if it was absolutely free since they were pressuring me to add a line (I already had a phone I could use).  They answered yes every time.  What they didn’t tell me is that you get charged for it initially and over the next two billing cycles they will eventually credit what you’ve been charged.  And they also forgot to mention it was only good for one year.  The “free” phone ended up costing me double the two phone’s i started with.  They got really ugly words from me.  Deceit is so wrong!!