I mentioned the process required to remove these keys in a different post, but it is important to try and be careful with the plastic scissor clip that functions under the key itself, as it is quite delicate.
But it is designed to have one end of the key slid into place, and the other end clicked in. If you lifted the keycaps from the top edge and pulled hard, you more than likely either tore off one of the little plastic pegs from the scissor clip, or damaged the alignment slots on the underside of the T key.
Do you have a photo of the underside of your keycap and the gap where the T key goes so i can inspect both the key and the scissor clip in situ? i may be able to identify the damage and suggest a solution to fix it.
Otherwise, it'll be a process of sourcing a replacement keycap with its scissor clip and swapping it out. the issue is, with the magic keyboard being such a new product, faulty keyboards are in high demand and are hard to come by, so we haven't been able to get stock of the keys on their own as of yet. but hopefully its not too damaged to work with.
I hope this helps.