Shoaib Sayyad, Maybe try a system restore, back to when the card reader was working. Check if the card reader is disabled in BIOS settings. At the first screen after restart, look for a key to press for Bios or Settings and verify that the card reader has not been disabled in the Bios settings. The links below may also help with your issue. Good luck.
I hope this helped you out, if so let me know by pressing the helpful button.
https://community.sony.com/t5/VAIO-Software-Other-Operating/SD-card-driver-not-reading/td-p/127449
http://www.windowscentral.com/sony-dont-update-your-vaio-windows-pcs-windows-10-yet