Hi, I have got the same problem. It says something like "data or username failure". The verification slider does not show up at all.
Does anyone know a bit more?
Edit: Somehow it began to work again by itself, strangely.
So the solution could well be:
1. Check if the app is updated, or reinstall it respectively.
2. Restart your phone.
3. Wait for several hours so the system "boots up".
4. Try to login again.
5. If the login problem continues, try and contact Solarman helpdesk.
But usually this problem is just temporary – mostly caused by an ongoing update which is carried-out by the developer.
Regards