SanDisk SD-Card Extreme 64GB comes broken 2x

I just bought 2 SanDisk Extreme 64GB and neither of them worked, I put it in my iMac and it was unreadable, I went into disk utility and tried erasing it but it fails to erase:
(POSIX reports: The operation couldn’t be completed. Input/output error. : (5))
It does not have write protection on it, this happened with both of them.

Hi @Unknown000,

Please refer link to contact respective support team for possible replacement :