Sorry, but I misunderstood your situation.
If this is being put up by the program, and the program is freeware, my guess is you will not be able to stop it and without having the thing to play with in person I have no idea how you'd access the overlay. If the program is paid, it's outrageous that it would present ads to begin with, and I'd complain loudly to the software maker.
Brian - Windows 10 Pro, 64-Bit, Version 1903, Build 18362
The color of truth is grey.
~ André Gide