Irregular Period on Birth Control

I started the Yasmin 21 day birth control around April or May because of my PCOS. My gyno said it was okay to start with it straight away and that I didn’t have to wait until my next period (it’s been at least a week or 2 after my previous period).

6 months later, I still hav irregular periods and spot irregularly. Majority of the time the blood is brown and I do get normal period blood every now and then but I feel like there’s no pattern and I miss the regularity of my old period bc this is just getting frustrating Bc I cant predict when it comes or not so I’m forced to wear a panty liner all the time.

Has this happened to anyone else? Did you overcome it?