1. Check if your contacts have been set up correctly in your Contacts application.
2. Confirm that the settings you have chosen to sync your contacts are compatible with your device.
3. Make sure you are connected to the correct account when adding contacts.
4. Try disconnecting and reconnecting your account so that it can resync.
5. Force a sync by going to your phone's settings and tapping Sync contacts.
6. Check your contact list to ensure that the changes have been made or check your account on your respective phone and computer to make sure contacts have synced.