Why is my contact list doubled?
Duplicate contacts are really common, and they happen when you're syncing contacts from multiple sources like the cloud, your email, or social media sites.
How do I fix duplicate contacts?
On your Android phone or tablet, open the Contacts app . At the top right, select the Google Account that has the duplicate contacts you want to merge. At the bottom, tap Fix & manage Merge & fix. Tap Merge duplicates.