[CA] sick time balance went to negative after using 16 out of 40 hours.

[ USA, California]

Hey all, I tried using a sick day a while back that got approved (I have my approval letter) HR couldn't pay it out because it showing i have a negative balance. I went back and checked how many days I used to make sure I didnt go over but it shows right after I took 16 hours my remaining balance of 24 hours changed to negative.

I already talked to HR and they said they're aware of it but didnt do anything to rectify the issue which doesn't seem right. She basically just told me that they can't pay it out because it showing a negative balance.

Is there anything I can do to get this issue fixed? I guess im asking you guys so I can talk to HR again if I can.. they don't return my call or text so its really hard to get ahold of them and I want to be able to have all the information need to talk to them about this.