Always remember to upgrade the latest firmware and download it directly from the official website before any action done.
If you are using a 64GB Micro SD card, please format it to FAT32 on your computer first.
Memory type a SD, format it to FAT16 on computer
Memory type a SDHC , format it to FAT32 on computer
Memory type a SDXC, format it to FAT32/exFAT on computer
Memory type a SDUC, format it to exFAT on computer