Well u need to figure out if it's the SD card failing or if it's the phone failing...

So buying a new sd card asap needs to happen to u can be sure it's that card that failed.

In my opinion if its the phone that is failing then u actually have a big issue and u should be working on getting a new phone thru warranty.

Although if it's just the card... Bring it back to best buy and exchange it for a new one... Simple as that, don't try to fix it, i imagine at this day and age u backed everything up to the cloud that was saved on it.

If the card broke just randomly like u say it did best buy will exchange it no problem but if they don't just buy a new one.... It's 20 bucks. which is not worth doing all this research and trying to call the sd card company and get it replacd under warranty and all that. Buy a new one. Case closed.

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