If you don’t want to receive text messages from a certain person, you can block their number on your T-Mobile phone. Blocking a number will prevent that person from sending you text messages, but it won’t stop them from calling or messaging you through other means. To block a number on your T-Mobile phone: 1. Open the “Settings” app on your phone. 2. Under “Phone,” tap “Blocked Numbers.” 3. Tap the number you want to block and then tap “Block.” 4. If the person has already sent you a text message while their number is blocked, it will be deleted when you block their number. 5. To unblock a blocked number: 1. Open the “Settings” app on your phone and under “Phone,” tap “Blocked Numbers.” 2. Tap the number you want to unblock and then tap “Unblock.” ..