As can be found in your terms & conditions for your contract which you acknowledged, the cancellation must be provided in written form and in due time.
I don't think that there is too much of a chance to have a (way too) late cancellation accepted and the contract terminated by 2019 now.
Why precisely would you not be using the connection any more? Because "I'm not using it." is not too much of a valid reason.
What good was the posting of yet another thread yesterday night, @Jude? And why would you try to shift the blame for the contract extension to Vodafone? You alone messed this up by waiting until the (as it seems literal) last minute to cancel a contract you had wanted to cancel for pretty much a year.
If I were you I would also refrain from posting false accusations like you did in your second (archived) post or complaining that a German company has German as their primary language of business in spoken and written.
Just asking: If I went to your home country and wanted to sign a contract for something, would they give me the whole paperwork in German, explain any- and every thing in the contract in my mother tobngue and have a German speaking agent available at any time should I need assistance? See what I mean? Thanks.
