I think that at this time I would try a reset.
The standard procedure is
- Power off using the on/off button, make sure that the battery is charged (TT recommends to charge the device for 2 hours before doing the reset, that does not make much sense to me, but let it charge for sometime anyway);
- Remove the SD card;
- Use a paper clip to press the reset button (on the bottom of the device) for at least 15 seconds;
- Press the on/off button for at least 5 seconds;
- Insert the SD card.