Editing a contact's address doesn't remove the old address.

[Android Central Question]

I can add a new address to replace the old one, but the old address still appears in the contact details.

 

[methodman89]

Depending on your synching settings, you may be adding the old address back while also now retaining the new information /address. Adjust your settings and manually sync to clear the old data. Then retick the auto backup how you want.