How to merge contact list from iPhone to ipad

Have the same email account that your have on your iPhone, in iPad too because....

Contacts are neither stored locally on an iPhone / iPad nor in SIM. They are synced to an email account that you had Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other

1. How many Contacts account (email client server) you have?
2. What is your default Contacts Account?
3. Which email account you are using to store Contacts?

• See the GIF below for Contacts and Default Account

• Learn how to add an email account and make it default (Watch the GIF)
• This example is for Gmail but the process remains same for all Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other