I've got a new SD card (a cheap one) it was working fine at first but now all my photos & videos are being replaced with a circled white explanation point & grey background. I've only used 16 of the 256 GB. I post videos to YouTube & have 2 small children so I use my camera often & every good video lately is lost. Today is my daughter's 2nd birthday & the video of her leaving before school not being viewable is the last straw. My cloud is synced with my phone & as far as I can tell, none of my apps can view them. Can I recover these, HELP!