I've never updated firmware before so this is from a noob's perspective.
The user manual I have (copyright 2018 no publish date or version) has instructions about updating firmware on page 8.
DOWNLOAD the Firmware file (Zip format) from the Palstar website,
.
404 The requested document was not found on this server.
I think it must really be?
OK, I found the latest firmware (and only the latest) so I downloaded it.?la-1k_firmware_1_05B.zip
Extracted it, and it created a folder named?V_1_05B and nothing else from the root of the zip file.
Inside the folder are 4 sub-folders and a text file.

Following the manual, I connected a USB cable to my PC.
DOUBLE-CLICK “LOAD_LA-1K” within your LA_1KFIRMWARE folder that you
created in Step 2 That file doesn't exist in the extracted files.
Do I have an old manual or is the zip file incomplete?
Danny
K5CG