I have Unity Ads already configured in my project and want to Add Admob mediation

Hello, I was using Unity ads and configured it correctly ,and working perfect. Now I changed my mind , since I can not Add mediation on top of it. And Migrated to Admob. to integrate Unity ads as a mediation source in Admob I should import a unity ads package. which make duplicate Unity ads files in my project. I deleted Unity Ads under Assets Folder . but I does not solve the problem. what I should do in this case? Please help. my game is on play store , and Ads are not enough displayed. so I want to add sources