Help with Function Script

Hi guys I'm fairly new to Auto-It I understand the basics like mouse-click  sleep, winwaitactive() etc. and I'm attempting to move outward and start using hot-keys and functions but keep running into the same error.



here is the code

$Test = "{F1}"
HotKeySet($Test, "_Test")
Func "_Test" ($Test)
$A=0
Do
MouseClick("left",1119, 685, 2, 0)
$A=$A + 1
Until $A=1
$A=$A - 1
EndFunc

any help, tips and things I could do better will be gratefully appreciated thank you in advance.