Ap studio 1 . Bill acceptor only accepting 1 dollar and saying exact change only with a filled coin mechanism

[Matthew hernandez]

Hello guys recently i bought a Ap studio 1 snack machine. When i got the machine everything checked out good. But now im having a few problems. With the coin mechanism full and working it said “use exact change” with putting in a dollar and trying to buy a 75 cent  selection it shot the money out. But then i put the dollar back in and selected the 75 cent selection again and then it worked and even gave me change back. Another problem i ran into is that the bill acceptor is only accepting 1 dollar. I putt all the selections to 2 dollars to test it and it still only accepted one dollar then the green light turned off and it would not accept anymore money. I tried for the coin mech to flush everything out and buy products with a empty coin mech but it didnt work. So if anyone can help that will be greatly appreciated. Seems like the vending repair people around me dont know what to do.