Sorry to hear that. I hope that they did not "kick" you off. The topic was available on TA forum since a few weeks but there was no communication from VisitBerlin website.
This is an example reason why I and others always recommend to check BVG journey planner at day of journey, e.g. after landing with free airport wifi while waiting for luggage. The journey planner is the only tool which gives you the most actual information. GooMa for example did not ever realized that we had full day strikes of BVG, also not CityMapper. Just use the local provider info by website or app - best you can do for your journey.
Also other lines changed. e.g. bus line 200 (pdf) which some tourists used for sightseeing. It is no longer driving through "Unter den Linden", the boulevard between Brandenburg Gate and Alexanderplatz. Now it drives along Leipziger Strasse.
New is bus line 300 (pdf) from Potsdamer Platz via south corner of Alexanderplatz and along East Side Gallery to station Warschauer Strasse.
Some other basics and tips on Berlin's public transport.