I have saved files to my SD card via Rep G and they appear on the SD card but which show on my PC as ok on the card....but cannot be seen on my flash forge creator pro LCD screen. Therefore I can't print from my SD card on printer. What am I doing wrong?

My printer won't recognize files on my card. The only files i can access are the files on the SD card that came with the printer. Most is in Chinese which I don't understand or read. I have tried another SD and it won't work either. Frustrating. Flash forge makes a great machine but the instruction manual is poor!