Google has updated quite a few apps today. One of those is Google Voice. It’s a bug fixing update, but it’s a pretty significant one. It fixes delayed SMS notifications and inbox syncing issues. The inbox syncing issue caused duplicate notifications because they were not being cleared on other devices when you checked them on one. All this is fixed now, and the app should run fine. Hit the source link to update the app, or open the Play Store on your device(s).