Mobile phone

Source: http://www.freeimages.com/photo/mobile-phone-1243113

Even before we moved to Switzerland, I had a mobile phone subscription in the Netherlands with a major telecom provider. I liked this subscription very much, it was cheap and the credit was more than enough. I only use my mobile phone for texting. I rarely use my mobile phone for making phonecalls. For example, I only call my mother on her cell phone when she's in hospital, or in other emergencies. When I use my mobile phone, it's definitely from home and not on the road, because there's too much noise on the way to understand something.
So I usually prefer to call with our landline phone so that I can use my Bluetooth system. Using a Bluetooth connection between my streamer device and the phone, I can hear the sound over the T-coil when making a phone call, which noticeably improves the voice quality. Strangely enough, this doesn't work on my mobile phone and I have to switch on the speakers when I make a phone call. This means that everyone can listen in and that is another reason why I only use my mobile phone at home.

At the end of last week, I received an SMS from the telecom provider saying that my subscription will be changed.
The text message also said that they had sent me a letter or e-mail some time ago to announce the subscription change. But I did not receive any letter or email, otherwise I would have known about it and could have taken measures.
What's going on: many things are getting better, says the telecom provider, but I can't take my credit with me. That means for me concretely that I am starting from the 8th December my assets of over 100.00 euro loose. *
Since I hardly use my mobile phone to make calls, I use less credit than I get and as there is a new credit on my account every month, my credit has grown quite a bit lately. Now, however, I must have used it within three weeks, otherwise it's gone. I'm sure you'll understand that this is making me very angry.

Today I looked at the website of the telecom provider to see if and how I can complain. If I contact them by e-mail, it takes about 10 days - yes, you read correctly: 10 days - until I can expect an answer.
Calling is of course possible, but that's not a good option for me in such a matter. You can also chat (over mobile phone, of course) but it takes up to 3 hours to get an answer. There is no formal complaint form.
„Or you can also contact us via Twitter and Facebook“. Not really the right medium for complaints of my kind, is it? Or maybe I should do just that so that it becomes public how this telecom provider deals with its customers. In an Internet forum, however, I read that there have already been several complaints and the telecom provider has not yet paid back any credit. With my complaints, I won't have much of a chance.
For me this is all a reason to cancel my subscription with this telecom provider. Fortunately, I have a flexible subscription and I can cancel every month without having to wait. The disadvantage is that I will lose my credit anyway. And, if I'm in the Netherlands, I have to use my more expensive Swiss subscription. But I still have until December 8th to think about what I am doing and above all to spend my credit. Please, wish me good luck!

* The original post in German language, was posted on 23rd of december 2015