Addendum:
Now I use the pan for 10 months, I have to revise my opinion unfortunately.
It now depends on everything. The bottom has curved inward, ie inside it goes into the middle up, down he goes also up, so that a cavity is formed and the pan just at the edge is on the hob.
So I can definitely not recommend further the pan.
Amazon says that I am to contact the manufacturer.
But that's too complicated - I had some time ago with another one-off items.
I would also not a substitute, to the I have to probably having trouble again.
I'll scrap the pan and another me - hopefully better - get.