If a Linked Account is marked as "Incomplete," that means that the user may have inputted their credentials but it hasn’t gone through our validation step which ensures that the credentials are valid. You will know that the Linked Account is complete once the user sees the “Successfully Authorized Integration” screen on the Linking Flow!
There are a few reasons this can happen, so you'll want to confirm the following with your user:
Username and Password are correct
Each step was followed correctly in the flow
The API key was generated by an Admin
The permissions have been set correctly for the relevant endpoints
Person logging in is an Admin of the platform
If these steps don't resolve the issue, feel free to reach out over Intercom!