Hello,
For further troubleshooting, please, execute the below command in Windows PowerShell on the computer where Adaxes service runs and provide us with a screenshot of the output.
Get-InstalledModule "ExchangeOnlineManagement" -AllVersions
Also, please, provide us with a screenshot of the Multi-server environment dialog. The dialog displays how many Adaxes services you have and what their versions are. For information on how to view it, see https://www.adaxes.com/help/MultiServerEnvironment.
You can post the screenshots here or send them to us at support@adaxes.com.