How to move email from old account to current account

[WiloDeals]

 I originally set up account using my business email until my husband convinced me to set up my website on his account so we could manage his and mine under one account.  His email is primary on this account.  Problem is, I can't link up certain sites like Facebook in my Shopify store because my business email is still connected to the other account I set up.  When I try to change his email to my business email, Shopify says my email is already taken.  I tried to deactivate my old account, but since I never verified that email, I can't even get into it to do anything about it.  

So how do I get Shopify to deactivate/cancel my original account so I can bring my business email into this account I now share with my husband whose email isn't being used for anything other than login?