No Share to Teams button in outlook

We are currently rolling out Teams for a customer. The "Share to Teams" button or addin isn't available in outlook, however it is available in outlook on web. Already logged in to Teams with the same account. As per Microsoft the addin should get automatically installed. Teams meeting addin is already installed and working. Outlook version used is Microsoft Outlook 2019 MSO(16.0.10392.20029) 64bit. Are there any requirement for the office or outlook version for the addin to be available? I have done some research however couldn't find any concrete answers on the versions or requirements for this addin to be enabled in outlook. Any help or suggestions will be much appreciated.