Biotrim Labs — testoultra testosterone enhancer scam

Address:

P.O Box 1201, 519492

I placed an order with biotrim labs for one bottle of testosterone enhancer on 8th dec 2019, based on their advertisement of s$29.95 per bottle. It was clearly stated that shipment is free if we order on the same day.
After a month, 6 bottles of the said product was sent to me. One day later, my bank sent me a bill from this company for s$208.75.
I intermediately wrote to my bank to dispute this charge (Which is still outstanding)
Several mails to this irresponsible company drew no answers until i threatened to report to the police of their malpractice.
They replied and said i ordered 6 bottles and therefore was charged s$208.73. They insisted that i ordered 6 bottles, when i am sure i ordered one bottle for s$29.95 (As advertised). They claimed they sent me an invoice of which i did not receive. If i had received this invoice, i will immediately dispute the amount and the units ordered, thus preventing the scam.
I want a refund of s$178.78 ($208.73-$29.95)