Please read the thread again. I was trying to correct the post above mine which had two errors in saying 'You need to get Sandisk Extreme 64gb not Extreme plus.' The 64 (capacity) doesn't matter and any of the current Extreme/Plus/Pro cards could be U3 so both points were wrong. Also you are incorrect when you state that all Extreme cards are U3 as there are still Extreme U1 cards available for sale and the OP didn't specifically state which one he had. The Sandisk Extreme/Plus/Pro designations can be confusing as their capabilities have changed over time so I was just making a general comment to look for a U3 card rather than a model name.
SanDisk has a lifetime warranty on Extreme cards (as long as it is not used in continuous video/datalogging devices) in the USA and most countries so if it is bad it can be easily replaced. But try formatting in the aircraft first.
Your experience does highlight another possible problem, and that is the number of counterfeit cards out there. Only buy from reputable retailers, and this may not be a good product to buy on Ebay.