If you are having trouble adding more boxes for additional phone numbers and email addresses, then you are probably using Microsoft Internet Explorer.  IE has been discontinued by Microsoft.  The final version has an issue processing some web controls, which breaks our "Add a (email/phone/address)" function.  You should upgrade to a modern web browser such as Google Chrome (which currently has 85% of the PC browser market), Safari, Firefox or even Microsoft's replacement for IE, called Edge, available only in Windows 10 and above.  The issue will go away.