c# Windows Forms - buttons with texts on Data Grid View displayed half transparent. Why?

I have a Data Grid View and some buttons with texts on it, using Metroframework for design. The letters are somehow half transparent that the background color is seen through those letters - when the background is red it is half red and so on. In Windows Forms setting, I changed the font color - fore color to black, set opacity to 100%, and yet none of them worked. Any help is appreciated. Thanks in advance!

Solution

Oddly, it has been solved after I redownloaded the file from the repository.