A few things to keep in mind for mobile number change: You'll receive a free text message with the new mobile number. Once received, please turn your phone off, then back on. Mobile number changes are completed within 2 to 4 hours. Your voicemail box will be deleted and all old messages will be lost, so make sure to save voicemails you wish to keep. You must set up your voicemail greeting and password again. The voicemail password will be reset to the last four digits of the new phone number. If you have a My T-Mobile account, you don't need to re-register. Your existing password works with the new mobile number. Call records for the old phone number will no longer be available on My T-Mobile. Wait 72 hours after the mobile number change before accessing My T-Mobile with the new number.
Shall we proceed?