App store on iPhone lost all purchases

I had been using a very old email address for my apple account, and recently learned that I could change my email address linked to my apple account. So I change my email address, do the email verification only to find all my purchases has been lost! ):

when I go to app store on iPhone and into the 'Purchases' under updates tab, theres nothing.

When I search for an app that I know i've already purchased, it doesnt have that cloud logo but instead asks me to pay for it again.

has anyone had this problem?

I've invested hundreds of dollars into apple's ecosystem and I'm very upset D':