Pathplanner PID

So our team got teleop working on swerve and we decided to do pathplanner. We did this last year without any problems. But we are having terrible luck with PID. Last year our PID for drive was (3, 0, 0). This is not working on our robot and we are looking at all types of PID tuning and nothing is working. I decided to look on github to see other PID values to base it off of, and noticed no one used ID the just use P. Is this a normal thing, or are we just having really bad luck with our robot this year? Also any tips for tuning PID?

Thank you.