Flight postponed for 1 day, no money back, no response any more

Our flight , nearly 3 months now ago, was postponed for 1 day and we did get the notice per mail at 16:30 and the flight should start at 08:00 in the morning the next day. So instead of 8 days holiday we only had 7 days and that at such a short notice.

It took me nearly the whole next day to get new tickets and rearrange the rental car and the hotel.

When we got back, I talked to the customerservice and then we had several mails regarding this. (I also had to send the passportcopies twice). I gave them a list with our extra costs because of the postponed flight (but my extra time I spent for rearranging everything was for free, of course)

At least they wrote always back, since about 2 weeks nobody is responding anymore altough they promised to give us feedback a week later. Then nothing happened and there was also no response on my last 2 mails.

This has nothing to do with good customerservice and I really urge them to get back to me.