Primastrom = Scam

I got lured into a 35 EUR/month guaranteed energy for 24 months by Primastrom a few months ago. It was a telephonic conversation. I was not interested in switching from my earlier provider, and hence decided to tear away any contract documents that I may get from Primastrom and communicate that I'm not interested. I then received the contract papers, which I communicated them to excuse me from as I had not signed on any paper. Moreover they didn't have green energy. They wrote back saying "agreeing on phone" is good enough for them to start a contract. I went to my then local green energy provider and they said Primastrom has ended my contract with the local supplier. I was then left by nothing else to do but go ahead with Primastrom. In October the promised deduction of 35 EUR was made. November: 57 EUR December: 57 EUR

I wrote an email to Primastrom asking for a justification. They replied saying their customers should bear the costs of the new energy price changes.

Then comes the deduction for January: 97 EUR!!!

In none of these have they given a prior communication of an increase in price. This also seems to flout the mandate set by the Bundesnetzagentur about communication, where I have lodged a complaint last week.

Some reviewers on Trustpilot (ratings for Primastrom are shit-deep) have suggested to take the Bundesnetzagentur route for help. Some have also suggested taking a legal route.

Has anyone here faced such price-crisis by Primastrom or any other energy provider as I have? How did you deal with the companies? Any help in this regard is greatly appreciated.

Personally, this has taken a huge toll on me and lead me into a depression.

P.S. The first telephonic call was from somebody at the energy department who explained the Primastrom offer in English. Then he said he would be recording a conversation in German in which I should be agreeing to the offer made by Primastrom. As you may have guessed by now, an English explanation was necessary because my German isn't good.

Edit: my yearly energy consumption is about 1250 kWh.