unacceptable customer treatment

I have a verimark orbitrak that had a problem, I initially contacted the manager, of the store he said that I must contact verimark directly, so I proceeded, I spoke to the lady at the verimark headoffice and she instructed game kathu to give me a new machine, by doing this the customer did game kathu job. So I went to the store on Saturday 25th April 2015, whilst there I noticed a treadmill, that was there for R 4500 so I decided that go for the treadmill, the manager Aron spoke in front of my family that that was fine and that I can also get a discount for the unit since it was a demo, so I was happy with, I left the shop after waiting g almost 2 hours for them to make a decision. On Sunday morning at around 09:07 am I received a call from Aron, who said that they cannot help me with the treadmill, they can only help me with the exchange of the orbitrak. I was ****ed as this un proffessional guy spoke lies in front of my family, he gave us hopes and now crushed it. , i went to the shop at around 10:00am and Sydney the stand in manager refused to come to the enquires department, now I was made a fool the customer. Please assist in correcting this matter