There are two reasons that will make gDMSS (DMSS Android version) show you this error message:
-you have entered a bad password: please check it / retype it
-someone has tried to access your account and it got locked
In both cases after you check that the username and the password are the right ones you should reboot your device!
If you have forgotten your password, you can use our DVR / NVR password recovery service.