We are aware of Meraki nodes reporting issues with dashboard connectivity within the EU region. If you have nodes losing connectivity to Dashboard and if your dashboard organization is hosted in Europe then it's most likely related to this. You can verify by scrolling to the bottom of the page and it would say which region your organization is hosted in.
End-user traffic should not be impacted by this. It has been marked as Sev 1 internally and we are working on addressing it with the highest priority. Please follow this thread for updates.
Updates will be provided below as a new comment to keep you updated.