Combo box glitching

I’m hoping someone else has run into this problem before. I have a combo box that works absolutely fine. Does exactly what it is supposed to. Where I am running into a problem is that when you select the combo box and the list drops down, the outline highlight stays around the first item in the combo box. When you select an item and the combo box collapses, the outline highlight moves to the are where the drop down list was. Leaving me with a an outline just sitting there. I’ve tried changing the theme/styles and I can’t figure it out.

Has anyone run into this before?

Thanks.