Hi Chayan, welcome to our Community! I looked into it for you and yes, your contract ended on the 16th of December. However, subscriptions will always keep running until you cancel it yourself (that way you will always be connected). You have a business subscription, so the only way to cancel it is through my colleagues from customer service for businesses on 0800-7112. They can cancel your subscription and please note that you always have 1 month notice period. So, you can still use your subscription for a month.
Please let me know if my colleagues were able to cancel your subscription! 😄