Do you have the from the sticker inside your TV?
Without more context, it's challenging to provide a precise answer. However, I can guide you on general steps to find firmware:
After writing a full firmware via programmer, you must recalculate the checksum or the bootloader will refuse to start. Most full dumps include a valid checksum at the end of the U-Boot partition.
Extract from your own device if it's still booting:
Note: Some versions will show an "Upgrading" progress bar on the screen.
: Use a high-quality USB 2.0 drive (8GB or 16GB is ideal) formatted to FAT32 .
Firmware is panel-specific. Using firmware meant for a 32" screen on a 55" screen can cause a "Negative Image" or an upside-down display. Match the Panel Model Number (found on a sticker inside the TV) with the firmware version.
While holding the button, plug the TV back into the power outlet.