If you’re like most people, you probably have a voicemail on your iPhone 6s T-Mobile. But if you don’t, there are a few things you can do to set up voicemail on your phone. First, open the Settings app and select the General category. Under the Voicemail section, select Add New Voicemail. Enter your name and phone number and click Add. Next, under the Type of Voicemail section, select voicemail. You can choose to have a voice message or an email message sent to your voicemail when someone calls. If you choose to have an email message sent to your voicemail, make sure that you enter a subject line that’s appropriate for the email message that will be sent. Now click Save Changes and confirm your settings before pressing OK.