Please make sure that your Micro SD Card is plugged in properly. Please try to uninstall the driver in Device Manager once again then go to Download drivers and firmware for Surface and download the .msi file. After installing the drivers and firmware please restart the Surface twice to apply the changes.
• If there's not an .msi file that corresponds to the build of Windows 10 you have installed, select the .msi file that's closest to your build number.
• To find out which version and build of Windows you're using, select Start > Settings > System > About , then look under Windows Specifications to find your operating system version and OS build number.
If issue persist, please run Surface Diagnostic Toolkit. It is a self-healing tool which looks for potential issues and fixes them, as well as ensures your device is completely up to date. Or manually check Windows Updates by going to Settings > Update & Security > Windows Updates > Check for updates. By the way, can you tell us the Version and OS Build on your Surface Device?