New Office 365 license split account

[janots]

Hi, 
Today I was going to add a new MS Office 365 Essentials license to an existing microsoft account where licenses for two MS Office 2016 for Mac licenses existed already. 
The result was that I ended up with two accounts on the same email and authentication issues as a result. 

I went to the original account and changed the primary email to create two completely separate accounts but now struggle with several problems.

1 - the teams button doesn't show in outlook 2016, despite restart of both outlook and teams. 
build version was 16.16. The license is Office Home & Business 2016 for Mac,
    - I'm not a wizz on Mac, but will I get 16.24 version just by running automatic updates? understand last update was run only a month ago.
    - Is there anything else I can do to get the synchronization and teams int

2 - In Teams, both the application and the web version, it keep showing an error saying "Can't sync right now. We'll try again soon." when trying to create, edit and manage meetings in calendar. 

[#2]

For issue #1, Try checking Outlook add-ins to see if the Teams add-in is appearing. There is a good walkthrough here: https://technoresult.com/how-to-fix-teams-add-in-not-showing-in-outlook/

For issue #2, the meetings option will only appear if there is a mailbox (Exchange Online) - can you confirm when you created the 2nd account, did you assign an Exchange Online license and sign into it? Make sure Teams is signed into the same user account as Outlook and then the Meetings should appear and work in Teams.