Getting campaignId's for users memberships using api/oauth

We’re building a oauth-integration with patreon to get information about which campaigns they are a member of. So far we got the oauth working, but when requesting the data as we understand the documentation the campaign info is empty. Is there anything obvious that we’re missing?

We request the auth token using the following scopes: [“identity”, “identity.memberships”, “campaigns”]

Using the access token we make a request to this url: https://www.patreon.com/api/oauth2/v2/identity?include=memberships,campaign

For a user with one campaign we get the following result:
{
“data”: {
“attributes”: {},
“id”: “29009124”,
“relationships”: {
“campaign”: {
“data”: null
},
“memberships”: {
“data”: [
{
“id”: “f29e647d-9458-4961-bd51-12b5bdaabf5e”,
“type”: “member”
}
]
}
},
“type”: “user”
},
“included”: [
{
“attributes”: {},
“id”: “f29e647d-9458-4961-bd51-12b5bdaabf5e”,
“type”: “member”
}
],
“links”: {
“self”: “https://www.patreon.com/api/oauth2/v2/user/29009124
}
}

The docs states:

If you request Campaign and memberships, you will receive information about the user’s memberships and the Campaigns they are Member of, provided you have the campaigns and identity[memberships] scopes.

I’m assuming that the scope identity[memberships]really should be identity.memberships, but other than that I don’t understand what could be wrong. Could it be that you need to specify the fields returned for the campaign?