WHERE DID ALL THE GREENBACKS IRAN IS SENDING TO HAMAS COME FROM ?

Repeated reports, originating in the Middle East, state that Hamas and Iran have patched up their differences, and that Iran has sent Hamas "tens of millions of dollars," so that it can reestablish its tunnel system, and rearm for another attack on Israel. Where did they get all those greenbacks ?

If the sanctions in place against Iran are working, it should be extremely difficult for Iran to lay its hands on $10,000,000 in cash, yet there has not been any serious effort, on the part of the United States, to shut down the two most accessible local sources for US Dollars:

(1) The banks and MSBs operating in the area controlled by the Kurdish Regional Government.
(2) Baghdad banks and non-bank financial institutions.

Both of the above jurisdictions, which are nominal allies of the United States, in the war against ISIS, and terrorism in general, appear to have been given a free pass when it comes to American interference in the lucrative illicit trade of dollars going to Iran. Obviously, international politics trumps sanctions compliance. I understand that, but the net result is that now Hamas is fully funded, and much more likely to start up yet another armed conflict with Israel.

Is there anyone in the Department of the Treasury who can initiate some program, in the field, to suppress the sea of US Dollars flowing into Iran ? Otherwise, Iran will continue to fund non-state actors who will continue to initiate more attacks, which will draw armed response, and we do again down the slippery slope to war. Is the US so afraid of offending its Kurdish allies ( who are also working with israel in several matters, by the way) that it neglects this critical issue ?