upgrade from gold to diamond
If you opened a ticket with support, it shouldn't take too long to get back with you.
Web works better with upgrades from lower tiers by crediting the balance to the new purchase. I think Android might do something similar.
Apple isn't as good but I don't know the exact process there. My understanding is it's an issue with the way that app store works. That said, are you sure both purchases were applied to the same account?
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