1. Please follow the steps below to solve your problem:
a. Make sure that the card reader is connected to the USB 3.0/2.0 port of your computer correctly.
b. Check "Device manager" to confirm if the system has detected the card reader. If it does, you will see ''USB Mass Storage Device'' under "Universal Serial Bus controllers."
c. Try connecting the suspected card reader to another laptop (this step verifies if the card reader is fine).
d. Try inserting another SD/ micro SD card to the card reader because some types of SD/ micro SD cards need more power supply than others.
2. Please refer to the link below to download the driver that is suitable for your OS version: