Admin API: Get user DIDServiceNumber from the admin API

Greetings,

We’re using this API to pull in user information. We need the DID number to pull it into a different system. The get user from account API does not pull in that attribute.

https://admin.api.mitel.io/2017-09-01/accounts/{accountId}/users/{userId}

Are we missing a parameter that is supposed to be pased with this request?