Summary
The impersonate mutation from the vtex.store-graphql app does not behave as expected when the customer was not created via the VTEX platform, but instead imported directly into Masterdata (regardless of whether it was via API, spreadsheet, or manual input). When this happens, the customer's profile data is not immediately available to the vtex.telemarketing app after impersonation.
Simulation
To reproduce the issue:
Import a user into Masterdata without (can be via API, manual entry, or spreadsheet).
Go to a store that uses vtex.telemarketing with a valid admin role of telemarketing.
Try to impersonate the new user.
Observe that the profile information is null in the mutation response.
Refresh the page manually. After that, the profile data appears correctly.
Workaround
Refresh the page after using the impersonate mutation, either manually or programmatically. This forces the profile data to be fetched properly.