Expanding canvas size

[Afterimage]

When I try to expand the canvas size on all 4 sides, PS expands the canvas on either 2 or 1 side. I have done this many times without issue. I have relative box checked and all the arrows are on. 

I am on an iMac with Catalina 15.3. 

I have reset preferenes and that did not work either. 

[Chuck Uebele]

You have the anchor point set for the center of the image? Can you show a screen shot of the dialog box?

[Just Shoot Me]

Place the DOT in the Center. Type In the number of inches you want to expand the canvas in each direction, Width + Height.