click the image if found on screen

hi im kinda new in this programming language i hope you can help me
im trying to automate a mobile android game

i want to click the violet image when it found and screen else if no violet found. click specified x,y coordinates of teleport skill



---- Main Program:

if(exist("violet.png")) then



click("violet.png)



else

  click(Location(987, 202))  -- this is the coordinates of teleport skill

end



then repeat it by loop but it doesnt seem to run
can you guys suggest what the best thing to do thank you