Dishonesty and ambush marketing by Virgin Active Centurion salesperson

I was formerly a member of Planet Fitness. I got an unsolicited offer from Virgin Active, stating that there would be no joining fees if I moved to them before end July. I signed the agreement in July, and submitted the signed agreement in July. I had to wait for the Planet Fitness cancellation to be processed, but again, my signed agreement reached Virgin Active before the July cut-off date. I was hounded by the salesperson at Virgin Active and pressurised to come and sign. When I went in to Virgin Active in Centurion, on 7 August (and again, I had to wait for Planet Fitness to cancel my previous membership) I was informed by the salesperson that "I had missed the special" - this being of course, completely untrue, as I had submitted my signed agreement before the end of July. He told me I had to now pay the R1000 plus joining fee per member. This is shockingly dishonest and, in fact, *******. It is known as ambush marketing. I am now in a position where I cancelled my Planet Fitness membership, and will now have to pay a joining fee there too, because I was deliberately misled by the Virgin Active Centurion salesperson. This is one of the most shocking examples of corporate dishonesty I've ever been exposed to, and I demand action.