I did what mistman said but, it's doing the exact same thing as before (the sprite moves to the top-left of the screen). I know that it's moving directly to the coordinates -1 but, I can't figure out why it's not moving up one.
Yeah, you just need SPOFS 0,X,Y after the code that changes the position. Generally you want to make calculations first, then display it second. (Which is what SPOFS will do)
Try this:
Y=Y-1 'Changes Y to itself minus 1
SPOFS 0,X,Y 'Places sprite 0 at the values of the X and Y variables.
SPCHR... 'Put the code that changes the sprite's image here
SPANIM... 'Animate the sprite here.
That's just a basic outline of what the code should look like, just fill in the blanks with what you need to animate the sprite properly. Hope this helps!