Recovering account

Unlike some Android devices, contacts are neither stored locally on an iPhone nor in SIM. They are synced to an email account that you had Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other

If Contacts were on iCloud, try this --> Restore contacts, calendars, bookmarks, and more using ...

Else Add the email account that stores your contacts in the IOS mail app and enable Contacts. If you have a corporate email account added through a profile on your device, please check with your organisation's system administrator.

With the limited information that you have provided, It is hard to even guess the problems faced by you. 

You may get faster and better responses to your query by --> Writing an effective Apple Support Commun… - Apple ...

Please re-post with detail so that someone else can help.