I want to unlock sim lock

To achieve that goal, only the carrier whom that iPhone is locked to can help you, if you're eligible.

See this support article about that matter:--> How to unlock your iPhone to use it with a different carrier – Apple Support (AU)

Regards

Giulio

Contact T-Mobile to get it unlocked. Only the carrier it is locked to can unlock it.

Link-> How to unlock your iPhone for use with a different carrier - Apple Support

Link-> https://www.t-mobile.com/responsibility/consumer-info/policies/sim-unlock-policy