I don't understand your color boxes. The tabs are across the top of the screenshot Tab 1 is Cues, Tab 2 is Report, Tab3 Invoice, and Tab 4 DMX. You click on the tab and then place items on that tab. A tab is like a different layout. Just covering the basics, like I said the color blocks are the only thing that looks out of place. Files are known to act crazy, if they are damaged. Under File click on Recover and see if that finds any errors.
I predict that this tab control touches or crosses the boundary line between the header and body layout parts. Move your tab control down until it no longer touches or crosses this line and it should work just fine. Since such a tab control is often used with Form View, you may find it simpler to remove the header layout part from your layout after moving all layout objects out of it.