Why do I get a 403 error when calling GET hubs for bim360 projects only?

Question

After successful OAUTH 3 leg authentication, when I call the

https://developer.api.autodesk.com/project/v1/hubs 

I get a list of hubs. The BIM360 Hub response gives me all the information I expect including attributes, id etc. However in the meta, I only get the following:

"warnings": 
    "Id": null,
    "HttpStatusCode": "403",
    "ErrorCode": "BIM360DM_ERROR",
    "Title": "Unable to get hubs from BIM360DM EMEA.",
    "Detail": "You don't have permission to access this API",
    "AboutLink": null,
    "Source": null,
    "meta": null

My end goal is to use the

GET https://developer.api.autodesk.com/modelderivative/v2/regions/eu/designdata/:urn/manifest

I have managed to navigate the folder structure and get the model URN for the project in BIM360 but when I call the manifest I get a blank response with a 401 unauthorized error. ^

I'm thinking the 2 issues are related.

I have followed the following steps:

• Created an app and ensured the BIM360, Data management, model derivative API's are active.
• Created a BIM360 admin account with access to a project. I have also ensured that I can navigate the project from this account.
• I have granted my app access in BIM 360 ensuring I have access to DOCUMENT MANAGEMENT and ACCOUNT ADMINISTRATION
• I have asked and received permission to become a developer from [email protected]

I also tried adding extra scopes to my authentication: data:read data:write data:create data:search

I've run out of ideas... Please can somebody help?