If you accidentally deleted a contact or a list of contacts, don’t worry Gmail now lets you restore Contact list to previous state within the the past 30 days. As Gmail allows undo option for a sent message similarly Gmail now giving second chance to recover your deleted contacts in Gmail too.
To restore contacts in Gmail previous state
1. Right click on + sign on the sidebar to expand Mail, click “Contacts” .
2. From More Actions drop-down menu select “Restore Contacts” and choose the time to restore to.
3. Gmail restores your contacts to same state they were at your chosen time, any contacts added or not existed at that time will be deleted but you can always undo this restoration.