PDF Controls being covered by React PDF when scrolled

[bribui]

I am using a combination of CoreUI scrollable modal and react-doc-viewer. When I scroll down, React PDF (at z-index: 2) covers PDF Control (z-index:1) and blocks me from accessing the PDF Control. I had to do a custom CSS to change the z-index to above two.

Can we have a property to access the PDF control class or is there a solution for this issue?