Hi r666mor, thanks for your post - sorry for the delayed response.
Sorry to hear you've encountered this problem as well. Have you been able to check that the app and your device's OS are up to date with the latest versions?
If that doesn't help please let us know what device you're using, and if you've been able to try a different device to see if that works or not? Also, are you able to sign in to your VM online account with the same credentials successfully?
Please keep us posted,
Tom