Keep holding the button until the "Software Updating" progress bar appears on the screen.
The string tpsk518dpb802 is not a random alphanumeric sequence. It follows a structured naming convention commonly found in: tpsk518dpb802 software update verified
: Built-in dual-band Wi-Fi and Ethernet (10/100M) . Power : Backlight power ranges from 35V to 94V, 45W . Software Update Procedure Keep holding the button until the "Software Updating"