Debt collectors- No invoice/statement

The sheer incompetence of your billing department is inconceivable. It's a joke and therefore will never touch your services again. Congratulations. We received one bill which was paid for after birth . Then 6 months later we are hounded for an outstanding r250. No invoice, contact the wrong people- useless. Now 1 year later we get debt collectors saying we owe R800. No invoice. Nothing. Its mind blowing how useless your service is. Incompetence is an understatement