Unauthorized Charging monthly Service fee

I have had my Jet account since 2011 and upon opening my account I was informed that there will be no monthly service fee which I was happy about. After 13 years of having my account with no monthly service fee, I found on my statement that as of last month I have been charged a service fee because TFG and RCS has taken over which is a breach in my agreement with Jet and of which I'm not willing to pay for. I have lodged a complaint with RCS and the complaint is not being given the attention that it requires and the service level agreement is not being honored. As per the consultant that called me by the name of Samantha, she advised that I'm not the only customer which raised this so my question is why are we not being treated fairly or be given the attention that our complaint requires? Failure to resolve this, I will refer this to ombudsman and FAIS as this is not what I had signed up for when I opened the account.