Multi display set up - apps opening on wrong display

[myuserid08]

I've had a 3 display setup for ages - but recently it hasn't been working as expected.
Every time I open up my web browser, it opens up on the display to my left rather than the iMac (center).

The monitor to my left should open up Excel - one to my right, Outlook.

Unsure how I correct this - searched and followed all the suggestions but still the same (iMac is the primary display).

Anyone else had this issue and found a fix ?

 

[BrianBaughn]

It would be great if you told us "all the suggestions" that you tried. Otherwise, folks will have to ask, "Did you try ____?"

Did you click and hold on the app in the Dock and set "Options" to open on the proper display?

 

[myuserid08]

Right click > options doesn't work on apps for some reason - all I have is "keep in dock" - "open at login" - "show in finder".

Figured it out anyway - unsure if it's a bug. I had to drag the application (in this case Firefox) onto the main display and resize the app manually (rather than double clicking the app menu). Once resized the apps stay on the correct display.