iXpand not detected after ioS 9.3.1 update

Mobile Accessories SanDisk iXpand™ USB 3.0
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it does work with iOS 10. 

There is a kb on the sandisk support site that says after upgrading to iOS10 the drive may not be recognized. power cycling the phone should resolve the issue. 

try power cycling your phone and see if the iXpand will then be detected.