[2021] Multiplayer Steam / Ubisoft+ not working

Hello,

I've been playing with two friends in MP several weeks on Season 1 and Season 2, and we chose to play again in Season 3.

Both of my friends own Ubisoft+
I have Anno 1800 + all dlc on Steam.

Multiplayer is not working anymore, at least not correctly.
If a friend of mine create a new game and set it to public I can join it, but since loaded game cannot be made public, it means we can not actually play a continuous game for several weeks.

I've been forced to pay Ubisoft+ in order to play with my friends and it works perfectly well.

On this link : https://anno-union.com/ubisoft-is-partnering-with-epic-games-store-for-anno-1800/
It is said that Steam user will always be able to play with non steam players, which is not the case.

Are the developpers aware of this issue? When are planning to solve it?
How can I get refunded for my Ubisoft+ fee that I was forced to pay for nothing? I don't care about other Ubi games, I just want to play Anno with my friends.

Thanks