When I plugged my USB stick into my laptop there was an indication that I should repair it. After I pressed repair, there was an indication that there was an error, etc. After that, he no longer recognized the stick.
does anyone know what i can do i don't want to lose my data.
Well, the stick was probably broken before and the repair didn't help.
Hopefully there was nothing important on it…
The "Repair" means that Windows reformats the. Definitely not a good idea. Windows suggests this if the file system can't be read properly.
You need a program that can still recognize files and assemble the associated data even if the file system is broken. Most of them cost a lot of money. "PhotoRec" (Photo Recovery) is practically just as powerful but free. Originally invented to save JPEG images from a damaged camera memory card. Over the years, however, it has been greatly expanded and improved and can therefore be used for almost all data types.
The program is also available for Windows, but it runs fastest (and best) e.g. On Linux. You can start any (even ancient) PC with Knoppix from CD or USB stick, Photorec is included with Knoppix.
PhotoRec can read the data medium "forensically", ie retrieve known document types (images, videos, off-office documents) even after normal formatting. So you still have a chance!