Small Bug or issue may be

hi, our team is working on Zoho subs and we came across a little issue. Zoho subs can allow or disallow duplicate client name which is perfect but we need to disallow duplicate email too. The issue is if you create a customer with different name but same email then if you activate the customer's portal page then all of his previous record will be erased which can be fixed by using api in code but we are deeply concern because our sales team do not have technical knowledge much and we don't like to take risk too. If there is any fix for this please reply.

Thanks,

M hasan