Unless I was in your class, doing the same project, there's no way I would be able to tell you !
If you want to discuss this class assignment in public, post the actual *.ACD file and describe the hardware involved.
The most common mistake I see with the ladder version of the PID instruction is that it is not executed on a periodic basis by the rung conditions so that the execution period matches the iteration period set in the instruction. Since you obscured the precondition data, I can't tell. But I do see that the instruction is in the Continuous Task so there's a good chance this is one of your mistakes.
PID instructions and tuning are a big topic, and there's a lot of experience here on the Forum to help. But you're going to have to put in more than one sentence and a screenshot.