Outlook.com and Office365 in one client not working

Hi Forum,

i have the problem with two accounts in one client.
first contact is outlook.com (live.com address)
the second account is a office365 exchnage online account (own domain)

when i now want to add the o365 account the client tries to login in the live.com domain.
even when i manually add the server URL he wants to communicate with live.com.

i also switch the account order - first O365 and then live.com. it works for several days then the emClient wants again to login to live.com.

Outlook, Thunderbird, Apple Mail dont have this problem…

any ideas?

Thanks

Best,
Holger