Windows 10 keeps changing my logon picture

Windows 10 keeps changing my local logon picture to my wife's picture.

My wife has a separate local logon on our desktop computers, as well as on our laptop computers.

We both have our own separate Microsoft accounts based on our separate email address. Both of our Microsoft accounts display the correct picture.

We both log onto whatever computer we are using locally, not through Microsoft.  

There are no pictures in the picture history directories.

I would really like to know how to fix this.

I've stopped sync on both Edge and Chrome. That seems to be causing other problems - freezing both browsers.