Radiant Creations Called to cancel but they could find no record Santa Ana California

I ordered a "trial sample" and paid shipping and handling. It stated if I did not cancel within the trial period (I believe 30 days) I would be charged. I tried the product, I was not satisfied and called to cancel within 2 weeks. When I checked my credit card statement, I was charged $89.95. I called to say I cancelled but was told there was no record. I told the lady I would send back then. She asked if I had opened the product and I said yes. She said they could not accept opened product. I asked her what the whole idea of "trial" was if I didn't try. She then offered me 50% off. I told her I was going to dispute the charge.