Final Invoice

A tech came to our home to resolve an issue with the internet.  He claimed we would receive better service if we upgrade.  The tech indicated the cost of the remaining service would not change.  The cost of the TV service charges.  As of today, the issue is still not resolve.  So I canceled the service but the wrong date was entered.  I called and was informed the date was changed.  I would receive a final invoice.  As of today, I have not received a final invoice.  Please advise.