Coffee creamer thief at work

We have a fridge at work and we all have to put our initials on all of our stuff. My creamer has my initials (not pictured) on top of the cap in red capitalized letters. I had bought my creamer a week ago and it’s already less than half way full😑 I was pretty annoyed. I slapped on the sticky note (pictured) and started marking off when I last used it. My supervisor think I’m being extremely petty but I told her I really don’t care. Whoever it is needs to stop using my stuff