Is relocation of dock required for multi floor mapping?

I took my robot upstairs and put it to mapping. Spent half an hour mapping, setting no-go zones, virtual walls etc. And when i got it back down to dock, all the progress went down the drain and it switched to me usual map. What's the right way to do it? I have dreame D20 ultra

[D20 Ultra] kindly help ^

L50PLUS. Please guide for initial set up. Can I do vacuuming first, then go.for mopping?