Delivering false expectations to students certificate instead of Diploma

I've registered with Oxbridge Academy for Occupational health and safety Diploma course and I received a call to be advised that they are no longer offering Diploma co**** and instead I'll study for certificate of which I register for a DIPLOMA. Fees I'm paying it's for Diploma co**** not a certificate. I've called in three times to log a complain and I was advised always that someine will revert back to me. Every month I'm being debited for False certificate co**** I didn't apply for.