Users unable to download update

I just released an update for our app. However I've received some emails/reviews from users stating that they are unable to download or open the update. Some have tried deleting/reinstalling but are still unable to open the newly installed app. Has anyone encountered this?

yep, got the same thing. All users with OS prior iOS 9 cannot download update (while deployment target 7.1+ )

Users unable to download update
 
 
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