so i re-created the app registration based on a suggestion from another thread, and now the test tool works.
2020-09-02 18:56:18,247 [1] INFO Open TestTool
2020-09-02 18:56:49,491 [1] INFO LOGINTUNESCANNING DEBUG Fetching Intune devices
2020-09-02 18:56:50,319 [1] INFO LOGINTUNESCANNING DEBUG Found 1 Intune devices
2020-09-02 18:56:50,350 [1] INFO LOGINTUNESCANNING DEBUG Scan Intune container with app Id 'my app guid', using email 'my account'
2020-09-02 18:56:50,804 [1] INFO LOGINTUNESCANNING DEBUG Fetching Intune devices
but it still wont work from the lansweeper website/service