Just left Germany, sent the cancelation form, what's the status?

Hi,

I left Germany last end of November and, as written here in some questions in the forum, I just downloaded the cancelation form in English, filled in and sent it together with my de-registration in Berlin (Abmeldung) certificate and a proof of job offer in Barcelona, where I came to live.

I only received an email in response yesterday, saying that my contract will be terminated on 06.03.2018 and that I'll be charged with a prorated amount till then. 

I read here that this would only be during 3 months after my contract termination request.

Can someone check the status of this in inform me what to do? I would like to cancel my contract as soon as possible, I'm ok on paying any prorated fee or something due to early cancelation, and of course I'll pay the pending amount for the mobile phone. If that is not possible, I would like to reduce my contract to the minimum monthly amount thill cancelation can be processed.

Thanks in advance,

Daniel