Iphone 4s factory unlocked but t-mobile sim card don't work?

Restored it through itunes, added t-mobile settings contacted apple, contacted at&t (not blacklisted) reset network setting turned off 3g turn on data roaming etc etc still noyhing.at&t sim card works fine but not my t-mobile.tried 3 t-mobile sim card nothing both att and apple confirm the iphone is carrier unlocked.

should i just trade it for a friends galaxy note 1 + sony ion unlocked?

Added (1). My friend has unlocked iphone 4s from att working with t-mobile. Even apple said it should be working but don't know why it isn't

Iphones don't work with t mobile sims. Try hacktivating your phone.google it.that'll unlock your phone