I cannot buy platinum. Have a question.

I recently had problems with my email account, so I created a new apple i.D. for my iPad. Then I changed my pocket legends account to the new email adress. But it will not let me buy platinum because the app was purchased from the other apple I.D., and I would have to buy the app with the new apple I.D. Which I cannot do because it is on the same iPad and you cannot load an app twice.
So the question is, if I delete the app from my iPad; then buy it again with the new account, will I still have my characters?

yes all information is saved online

I contacted pocket legends support but they have not gotten back to me yet.

Thank you.