While holding the button, plug the TV back into the wall outlet.
Try a different USB port or a different brand of USB drive. Ensure the drive is FAT32 and the file name is correct. tpsk506spb802 firmware usb link
Are you currently facing a issue, or do you just need to update the Android OS version ? How to Update Firmware on TP-Link Wi-Fi Routers While holding the button, plug the TV back
Follow these steps to link your USB drive and flash the new firmware: While holding the button
Press and hold the button on the TV's physical keypad (not the remote).