We could solve the problem in the meantime. 🤗 It was a combination of the instructions below and using admin rights.
Answer from the Robohelp support team:
Although you can successfully sign in to your Adobe account in the browser, the Adobe Account page appears to indicate that no applications or services are currently assigned to your account by your administrator. Also, it seems you are not signed in with the correct business profile(contract- xxx xxxx xxxx).
Could you, therefore, please ask your Adobe administrator to check your user account directly in the Adobe Admin Console and confirm that the required RoboHelp entitlement/license is assigned to your Adobe account?
Please note that signing in to RoboHelp using the administrator's own Adobe account is not necessary for this test. We need the administrator to verify the product/license assignment for your user account in the Adobe Admin Console.
Once the RoboHelp entitlement has been confirmed, please sign out of the Creative Cloud desktop application, close all Adobe applications, sign back in using your account/profile to RH, and check.
If the RoboHelp license is already correctly assigned but the Loading window still remains indefinitely, please let us know. Since browser sign-in works while the RoboHelp window fails to load, we will need to check whether the managed device/network is preventing RoboHelp from reaching the required Adobe authentication or licensing services. A network/proxy/security restriction on the managed device remains a strong possibility like- Intune policy, firewall, proxy, SSL inspection, web filtering, or endpoint security is interfering.
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