I am subscribed to O2 since September 2019 and I upgraded my plan to the partner program in January 2020 so instead of paying 19.99 twice, we'd only be paying 34.99. I thought everything went smoothly but then I only noticed that I have been debited both 19.99 and 34.99 every month.
Since there is a lockdown, the partner O2 store is closed and the customer service didn't really do much.
What can I do?