Hamas is a partner in the Palestinian government. The Palestinian government gets massive amounts of funding from the US. Therefore Hamas receives US government funding. Salaries of Hamas functionaries are paid by the US government-funded Palestinian Authority.
The Palestinian Authority, which receives US funds, even pays saleries of Hamas terrorists who are in Israeli prisons. It also pays death benefits to the families of dead Hamas suicide bombers and other terrorists.
As I’ve noted before and here ... Prime Minister Benjamin Netanyahu has gone to Congress before and lobbied to keep the funds going to the Palestinian Authority because Israel wants the PA in there taking care of the civilian government (and not Israeli soldiers having to). So ... it’s completely within the permission —and also— you could say “requirement” of Israel to keep funding the PA.
What neither Israel or the USA is doing is sending money or arms to Hamas.
And those are simply the “facts of the matter”.