ASAP Tickets complaint: Dishonest Charges and Breaking the law

I had purchased a round trip ticket, Dallas To Iran, which the return flight was cancelled, involuntarily by the Turkish airline which states I am entitled to full refund, but ASAP refused me unless I would pay some figure close to$500 penalty. Instead of a refund or booking me on a different flight, even a different date that I was willing to accept, ASAP booked me on a different date, but the most inferior flight, perhaps the cheapest for them, with 8 hours layover in Istanbul and overnight stay in Houston, plus $177. penalty which I was left with no choice but accepting it.
Originally ASAP charged me insurance for any changes in my flight and the sale woman, Unity said her offer is not good without the insurance. Neither were the truth.
ASAP engages in unlawful sales to customers, and when I complained, it wants to appease to me by issuing a $50.00 voucher to come back and repeat the same frustrating experience of buying ticket from them.
My flight ticket has cost me close to $2000 when ASAP could have offered a free change of flight through JFK with only 5 hours of layover, but the greed and profits as the priority prevented them to do so.