U can check `/manacrate history` ingame to see if it did open something. If there is nothing there or you didn't receive the item. Make a ticket. If you have any chat logs of you getting gifted the crate if not just mention that you don't in the ticket.
Open ticket | ManaCube...
U can purchase a rank upgrade ingame. So if you buy cubits on the store and then go to the /blackmarket u can upgrade your rank to mvp+. Currently u can not purchase rank upgrades on the online store