You need to contact Customer Care over the phone or have a live chat.
General Customer Care & Technical Support contact details:
- From your T-Mobile phone: 611
- Call: 1-877-453-1304
Customer Care representatives are available from 3am-10pm PT, daily and automated account help is available 24 hours a day, 7 days a week. If you are ringing about a technical issue with your T-Mobile service, call from a different phone so that they can troubleshoot with you.
If you are looking how to access your voicemail on My T-Mobile, read How to use voicemail on My T-Mobile.