1. Turn off/unplug TRB140;
2. Press and hold reset button, at the same time plug the power cable and keep holding reset button for about 5 seconds (mobile signal LED's should start blinking);
3. Download and install adb from this link: https://forum.xda-developers.com/showthread.php?t=2588979
4. Open CMD with admin rights;
5. Download rootfs.ubi (https://we.tl/t-ZRCwToaBb8)
6. Use cd command to navigate to the place where you saved the tlt-rootfs-trb1400.ubi file (Example: cd C:\Users\ma.ju\AppData\Local\Temp);
7.Then use this command: fastboot flash rootfs_a tlt-rootfs-trb1400.ubi ;
8.When it completes the process use this command; fastboot flash rootfs_b build/tlt-rootfs-trb1400.ubi ;
9.When it is done unplug and plug your device again, it should boot up as normal;