Sky city community struggling with cosmopolitan

I bought a house at sky city and being finance by HIP (housing investment partners). Cosmopolitan was the contractor. Cosmopolitan is failing for pay rates and taxes for water and electricity that was used when building my house. I receive monthly statements with high billing amounts. I then called ekurhuleni municipality on our area, they the ones that advised me that cosmopolitan must pay for those billing services they used on my account. I really can't get help since this is been going back and forth with them.