Amazon.com: 64GB Memory Card works with GoPro Hero 4 Black/Silver/Session - Sandisk Ultra 64G micro SDXC Micro SD Class 10 works with Hero4 Silver Edition / Hero4 Black Edition & Everything But
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What to Do if Your SD Card Says Full but Nothing on It
Fix SD card says Full or Empty | Repair - Recovery guide
7 Common GoPro SD Card Errors (And How to Fix Them)