You probably have what's called a looped file. The pointers to the bloxks of the file, at one point, point to an earlier block, so the program (chkdsk or whatever you're using to read it on the phone) goes back to that earlier point, reads forward until it gets to that corrupted block, goes back, etc., etc., and it will continue doing that until the universe ends or something breaks. (It's like finding "the end of a circle" - there is none.
If neither the phone or the computer can read any files, consider them gone. If you can read any files, copy them to another place (the PC's hard drive or the phone's internal storage). Then format the SD card and hope the corruption isn't due to a physical problem with the card. (If it is, it won't format.)
If it's a SanDisk card, you can try their live chat (upper right at
SanDisk Customer Care). Or you can run
PhotoRec on the PC, point it at the SD card (you'll have to learn a tiny bit of Linux - drives aren't A:, B:, etc., they're sda, sdb, and the partitions would be named sda1, sda2, etc.) But PhotoRec doesn't read the block list (or the directory, where the file names are kept, it scans the card looking for blocks that look as if they're parts of any of the files it "knows" (and it knows a lot more than you've heard of), so it can recover any files where the files themselves haven't been overwritten or corrupted. (The names will be on the order of File0001.jpg or File0002.mp3, so you'll have to look at at or listen to the files to see or hear what the file names should be. And
don't format the card before doing this. PhotoRec is forensic software - it doesn't write to the card, so in a legal case, the evidence has been untouched. I don't know why something like this is free - there are law enforcement departments that would gladly pay 3 figures for a copy, but it's free, and the wiki at that link has a thorough explanation of what it does and how to use it. [You can even recover files on internal storage if the phone is rooted. You just make an image of storage (dd is a utility in the kernel, and does it nicely), copy that image to a hard drive and run PhotoRec on it.] A great utility to have.)