Cant access Marketplace

When trying to open the marketplace I get following error:

No marketplace connection: Client error response [url] https://marketplace.owncloud.com/api/v1/categories.json [status code] 403 [reason phrase] Forbidden

I am logged in as admin, this is new since version 10.5 is available, but I am unable to update since during the update process the updater cant access the marketplace and fails.