How to debug with Visual Studio

My project was running fine in Visual Studio 2017 Pro. I can attach to unity and debug my project with breakpoints and debug codes line by line. However, since I added Bolt to my project, debug in VS seems impossible. Now, when I play my project in Unity with Visual Studio attached to it. It takes a minute or two before the project start (sometimes it takes forever). If I stop the debug mode in Visual studio, the project runs immediately. Is there any specific procedure I have to follow in order to allow me debug codes line by line in Visual Studio?