My iPad Air 4th gen won’t read my usb c sad card reader
Hello, and thank you for using Apple Support Communities.
You've posted from this article: Import photos using Apple camera adapters This article has some great steps to take if you've run into any issues.
"If you don’t see the import option
If you don't see the Import tab, follow these steps:
If you can’t import some content
Apple camera adapters can import multiple types of media files from your digital camera or SD card. If the format isn't compatible with iOS, you won’t be able to view them on your device, but can import them to your computer later.
Apple camera adapters can import only content that was captured by digital cameras. You might not be able to import content that was renamed, edited, or copied to the digital camera or SD card."
If you're still having troubles, try using another SD card reader if possible. If another reader works without any issue, contact the manufacturer of that card reader. Here's another great resource: Charge and connect with the USB-C port on your iPad
Best regards.