Monoprice printer with Lerdge board returns bad M20 reponse

What is the problem?
My printer returns a file list when I send M20 and responds with OK on M21. However the GUI does not display any files on the SD card, nor can I upload or initialize the SD card.

What did you already try to solve it?
I've searched google and the forums as well as he FAQ. I found a somewhat similar issue with an improper response from M20, Marlin responds with echo:SD card ok, but my printer just responds with OK. I'm going to try and write a script/plugin to change that and see if it works

Logs (octoprint.log, serial.log or output on terminal tab, browser error console ...)

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ...)
Printer: Monoprice Delta Pro Lerdge X Mainboard running Lerdge firmware. Octoprint 1.3.1/octopi 0.15.1
[...]
Send: M21
Recv: ok
[...]

Hi @johne3819!

This can happen when the filenames on the SD card contain some letters from another character sets. Try the card in your PC and see if you can read the filenames.

Thank you for the response!
I took a new sd card, opened it on my PC and deleted all the files. Then put a new gcode file on it. It still can't read it on the octoprint UI. I should note that I can see the files on the printer LCD screen, and print them