Welcome to Android Central! Insert the card into your computer and backup as many of the files as you can immediately, if they're important to you. Then try reformatting the card -- but if the card itself is failing, it might happen again, so it might be safer to just get a new card.
Originally Posted by
Agnulraon Weird though, because the files are readable on other phones and laptops...
Do you know that for sure? In other words, did you try opening every one of the files? The filenames might show up, but the files might still be corrupted, and you wouldn't know until you actually tried to open them on those other devices.