this is not an issue or bug
PlayStation Dual-shock controllers use different mapping to Xbox/(Standard).
I think right stick y is index 5 or 7 for dualshock
I cant remember what the mapping is but it is in a different order to xbox/standard mapping
you can find them all yourself by making a text box on the screen and updating it every tick with
"Axis 1-"&Axis(0, 1)&newline&
"Axis 2-"&Axis(0, 2)&newline&
"Axis 3-"&Axis(0, 3)&newline&
"Axis 7-"&Axis(0, 7)&newline&
and do the same for the buttons.
then run the game and you will be able to see what index each dualshock control is mapped to
you should still keep mapping for xbox/standard joypad though as this is what most windows users joypads will be mapped to.
If you want the ability to use dual shock then you should program some type of user option to switch between xbox/standard and dualshock mappng