Unwanted PopUP Advertisement is Opening

Hi Since I moved my website from Hostgator US server to Hostgator India server, I found so many popup advertisement is getting open from my website. Before I thought it is because of some plugin but after checking I found that the same set of plugin, I am also using in in my 2nd website which is running on Hostgator US server and does not have any such pop up problem.

As far as I see, I do not find any responsible plugin and theme in my website for this problem.

Please help me to find out the source code of unwanted pop up advertisement in my website.

I do not have any solid prove to make Host Gator responsible for this.