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They can not switch the extra storage to the new account
what you CAN do is switch the email addresses on the two accounts so that you start using the new larger account with the old email address. Or you can merge the two accounts and use the old email address.
this page gives detailed instructions on how to do either one.
the instructions are much easier to follow on a computer than a phone. But once you complete them on a computer it should work on the phone
I can do the phone call and even work on my computer to help fix it for you or remote into your computer but it may have to be late tonight or sometime tomorrow before i would be free to do it with you.