Hi @Katelouise
This is a customer community, so we can't see what you are paying for.
You should be able to do this in your account - your bills will show if there is still a device plan to pay.
Guide: My O2 - Website
Guide: My O2 App
If those are not clear, then all ways to contact o2 are in this guide
Guide: How to find help & contact O2
Please note, this is not customer services and we cannot access your account. Do not publish personal details (email, phone number, bank account).
Link to our guide on how to contact them can be found here
