Google Analytics

Dear Sir/Mam,
I have use the newspaper themes for my website. I have try to linking my web site with Google Analytics with google site kit plugin. but during this process I have seeing the error “Error: We’ve detected there’s already an existing Analytics tag on your site (ID UA-16201XXXX-1), but your account doesn’t seem to have access to this Analytics property. You can either remove the existing tag and connect to a different account, or request access to this property from your team.” thin I have remove Google Analytics script from my header.php and try to link again but problem is as it is.
I have try to find the wrong code in all theme editor but code is not find any file. Thin I find my website view source file and I have found a wrong code in home page website source file. I have try to find that code in my website source file but they are not present any where.
I cannot add new code without deleting old code. Please help me for deleting the existing old Analytics tag code/ script from my website. Tell me how can I found and delete from my website.

Thanks
Pankaj