AliExpress review: False sellers on AliExpress

I have made big buying in China with different platforms. So I already know a little about the transaction procedures.
Still I got trapped by a pretended seller of excavators.
Actually in this category there are systematically appearing two problems: the announced prices are way much below the finally asked prices and secondarily the sellers get the buyer off the platform by communicating via WhatsApp.
I was trapped by accepting a deal on WhatsApp. After having paid 500€ for initiating the production process, nothing went the usual way. No proof of the production of the excavator, no information about the processing. I had to ask every step and finally when I asked for proofs they send me definately false pictures. I asked to return on the Aliexpress platform for finalizing the deal - they just do not react. So I won't pay the resting 3000€ because it of the platforms I don't have any protection and the behaviour of the seller was definitely flawed.

I talked to AliExpress about the problem since they did not warn the customer about the risk of communicating outside of the platform, but they never where interested in the problem.
So I hope with this description that at least other customers don't get trapped as I did.