MIXVIBES Dj Community old forum

I've been using Cross DJ for 8 months and never had a problem. This weekend, I launch Cross DJ on my MacBook Pro (as I usually do) with OS X El Capitan version 10.11.6 and I get this message:

"Cross DJ" is damaged and can't be opened. Delete "Cross" DJ" and download it again from the App Store. The App Store is asking me to purchase it again. Please help!

The appstore remembers your purchases. Be sure to use the same account.
It used to be that you first had to select the software by clicking purchase but before having to confirm you see the info you already purchased the software.