This error appears when a user has already connected 5 devices and is trying to login with another device. Each user is allowed to connect with 5 different devices and 2 Private Keys at the same time.
In order to connect to a new device, you must sign out from one of the previous devices you've logged in or you ask your administrator to force log out one of the other devices.
In order to log out from each device, the administrator must enter into the setting section which is the to the 3 dots menu. Afterward, please click on the 'Manage Devices' option:
The list of devices will be shown. Click on the 'Log Out' button of the selected device:
After this device has been logged out, you will now be able to login into a new device.