Guangzhou to Beijing

Hi , I am australian citizen and I am traveling to Amsterdam with China Southern. The airline change my itinerary and now instead of going on a direct flight from Guangzhou to Amsterdam I am doing Guangzhou to Beijing and from Beijing to Amsterdam. Two agents from the airline has given me different information as one says I need a Transit visa and the other one says I need to aplly for a turist visa because this domestic flight. I am a bit confuse and a bit stress out as I can read on the chinese website that I don't need a visa.

Do I need a transit visa or a turist visa or not visa if I am doing a domestic flight from Guangzhou To Beijing to Amsterdam? Thanks for your help