Hello,
in that case where the files are corrupted there is no way to fully retrieve them because they never were created correctly. so in that case i suggest replacing the card with sandisk and receive a new one and unfortunatelly you will need to record the footage again.
you can ask for replacement through this link
http://kb.sandisk.com/app/rmaform/session/L3RpbWUvMTQ0MjM4OTA0MC9zaWQvTnQ4ZHRCd20%3D
