Please check the following suggestions:

1. Ensure that you can see stellarmate HotSpot network name in the list of networks detected by your tablet. If the stellarmate network is not listed, then check that StellarMate is properly powered.  Use the HDMI cable to connect the unit to a nearby monitor/TV and check for any error messages. Take a photo of the error and open a support ticket in order for our technical support to help you further.
2. Ensure Tablet is connected to the HotSpot (default password is stellar@mate) or connected to your Home WiFi if StellarMate Controller was joined to the Home WiFi network before. If the tablet is connected to your Home WiFi, do you know its IP address? You can add a device manually by its IP address.
3. Open http://stellarmate.local or http://10.250.250.1 from your Tablet/Phone browser and see if you can reach StellarMate Dashbaord. If it fails to reach, then the communication is not established between your Tablet/Phone and StellarMate Controller.
4. Open StellarMate Web Manager at http://stellarmate.local:8624 or http://10.250.250.1:8624. StellarMate Web Manager is required to connect to StellarMate App. If the Web Manager is not responding then this could indicate an issue in either the connection or StellarMate OS itself (corrupted image or disk). Connect HDMI cable and look for any messages on the screen and send them to support.

If none of the above suggestions work, you can always reflash StellarMate Controller with a fresh SM OS image. Please note that flashing an image erases all the existing content on the StellarMate Controller storage.