Hi nuesoft,
I notice that you issue is more related to Yammer application. I am sorry to say that I have not found some general solutions about this issue yet. I will keep on
research. Also, this forum catalog is concentrated on discussing issues more related to Windows clients. For Yammer issue, we have a specific forum for you, we could contact to our Yammer support here for suitable solution. Thank for your understanding.
Welcome to Yammer Support
https://community.office365.com/en-us/w/yammer
Best regards
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