iPhone, 14 eSIM not supportive

so I was trying to get my bill Lower by T-Mobile they was playing so I decided to switch over not knowing that my phone with my unlock for the last month or so I’ve been trying to get my esim erase so I can go back to my old services no help I talked to literally 36 people the phone is still stuck on Sim, not supported screen, at this point. I’m ready to throw the phone away because I can’t use it. I haven’t even had it for a whole year.