So here is the update after phone call from MS team.
It seems like they are not cooperating with Samsung to fix the issue and Samsung just blame MS as a developer of the app.
Samsung claims full compatibility with MS office 365 and you even have it pre-installed on the S series.
Then when you report problem they just don't care.
Microsoft support was little bit more supportive - unfortunately they also not care as long as you all pay for the service it ok they start bother if we all cancel subscription even then it would be very small percentage of users who have this issue and even less it really needs they not going to do anything about it.
SO there we go - al of us who choose flagship from Samsung to use it as portable work tool and MS office 365 with it is screwed as the fix for this is just not a priority.
You can tell as the replies from MS here are just not giving any useful information and support on the phone just wont let you in contact with whoever to debug online.