@Albert Avetisian Thanks for asking question! It seems you want to use diagnostic setting email send service, Could you please confirm you have enabled the diagnostic setting from Monitoring menu and added destination and Save.
Please refer to this doc link- https://learn.microsoft.com/en-us/azure/communication-services/concepts/analytics/enable-logging#access-diagnostic-settings
Also, for viewing the logs it seems you are using Workspace, you can see logs from Logs menu under Monitoring- and by using default query pack for email send request summary or any.
see- https://learn.microsoft.com/en-us/azure/communication-services/concepts/analytics/query-call-logs
For your reference added screen shot with steps to be followed, Let us know if issue remains.