Bug/Issue Wargroove 2 - an invalid unit order has been received

We have been playing multiplayer maps on mixed platform (1 switch, 3 steam) with the wargroove 2. We bumbed now a second time to this error "an invalid unit order has been received".

The maps have been "Emerald Haven" and "Falstino Ruins". The error has happened two times when unit "Air trooper" has been over a mountain tile and other player has moved troop over it OR the air trooper has been moved over a unit on mountain. The game allows this to happen and the player game turn can end. For the next player, units are moved and error on subject is shown. After that no-one can enter the game anymore. On both occasions the other gameplay platform has been a Nintendo switch and steam that has been running on MacOs.

Wargroove versions (v.1.2.5) are same and this was now our 7 multiplayer game with wargroove 2. Out of those games we have seen this error now 2 times.

to be excact:

1. For the first time my "air trooper" unit was on mountain and enemy commander came over it, then the error was shown for that player.

2. On the second time my "air trooper" unit went over other unit on mountain and I could end my turn in normal manner. On the next players turn, the error is shown and of course after that no-one cannot join the game anymore but just get the error.

edit: fog of war has concealed the unit on mountain on both cases.