Option buttons inside frames within a userform disappear partially when scrolling

I designed a Userform, that appears automatically when user opens the Excel file. It shows Questions as text labels and 4 option buttons and Checkboxs within a frame for each question. it's an exam (MCQs) form. I am facing the following problem: when i scroll down through the userform, the option buttons and checkboxs disappear, or incorrectly displayed, but they are there, so when you click on their locations to select them they appear!. The problem occurs mainly, when using 2 monitors (primary, secondary) and when i make the userform full screen.


my code is very long and complicated, but this is the part related to displaying the userform in full screen:

Application.WindowsState=xlMaximized
With UserForm2
.Height = Application.UsableHeight
.Width = Application.UsableWidth - 15
End With
UserForm2.ScrollHeight=(120*nq)+120
UserForm2.ScrollBars=fmScrollBarsVertical
UserForm2.KeepScrollBarsVisible=fmScrollBarsVertical
UserForm2.Zoom=130
UserForm2.Show vbModeless
Application.Visible=True

I also tried different ways to make the userform full screen, one of them for example using the active window height and width. but i got same result. Please note that this file excel (userform) must be distrubuted to students, and they run on their own computers, so any solution must consider that.
Regards,

perhaps try refreshing the screen on scroll.