If you have backed up and saved the contacts on a CSV or VCF file from Android with VeryAndroid Contacts Backup, you can restore them back to your android with ease. Here is the step by step guide:
Note: Make sure the CSV or VCF file is in this folder /sdcard/veryandroid/ContactsBackup/ on your SD Card before restoring.
Run the Contacts Backup on your android phone, and you will see this screen:
Click the "Restore Contacts" button:
Here you can select a backup file you want to restore from. Then click "OK" button to continue.
Successfully. All the contacts are restored back to your phone now.