Why can't I activate my Sell Voice account?

Issue symptoms

In my Sell Voice and Text settings I see an error message:

This job calls for some extra help! Contact Zendesk Customer Support to get Voice activated for your account, or try a different number.

Resolution steps

One sales rep can enable the Sell Voice feature for the entire account in their settings. If a sales rep experiences an error message, see the resolution steps below:

• An error message is presented if the sales rep enters a phone number they have already used to activate the Voice feature on another account. For security reasons, the same number cannot be used for Voice activation in multiple accounts. Use a different phone number to activate Sell Voice.
• The number must be a mobile phone that can receive text messages and must be entered in a valid E.164 format including the area code and country code. For example, if you have a United States mobile phone number you would include the country code +1 at the beginning of the number.
  • Correct format: [phone]
  • Incorrect format: 2223334444, 222-333-4444, (222)-333-4444 

Note: Only one user on the account can trial Sell voice using the default voice number [phone]. Additionally, trial accounts using SMS numbers are limited to 100 messages.