Forever billing me incorrectly

I am very disappointed with the service that I get from Planet Fitness including their call centre I was built incorrectly as usual and I am always left to call the contact centre where I get no help from agents I was told a manager would give me a call it has been 3 days and no one has given me a call each time I call and try and speak to a manager I am told that the managers are all busy or I am put on hold until the form drops or my airtime finish is the customer service that people get is pathetic and one should not treat people you get money from in this manner I am still awaiting a phone call as now I am receiving SMS is that my account is in arrears and if I don't want legal action to be taken against me I should contact the same contact centre that is not even bothered to help me with my query Can someone please help me because this is very unprofessional.