Help with us sda t-mobile on italian network

[Guest M4cch3]

hi all, i recently bought a sim unlocked us sda t-mobile phone, i put in my sim card (vodafone, but i also tried wind and tim) and it seems that he can't take the network, it's very unstable(most of time it's on searching network, sometime have 1/2 signal line power out of 5) and my all other phone have no this problem with the same sim.

so this is the question: there is same setting i need to change, is normal because is t-mobile phone, or it is broken?

Thx