First time printer here. So I'm having a problem where the files I've downloaded, put through CHITUBOX, sliced the files onto my USB, made sure they're .ctb, but for some reason, they're still reading on the printer screen as "unknown file format", despite there being other previously made (not by me though) .ctb files where the models themselves show up on the printer screen, but my .ctb files aren't? (They only show up as that three-papers-on-top-of-each-other symbol) What am I doing wrong? I've made sure to have the latest version of CHITUBOX installed, making sure they're the same files as the ones that are readable by the printer (.ctb), can anyone help figure out what I'm doing wrong/how to fix this?