Copilot Chat missing in Outlook Web and Outlook Classic

Hello,

since recently we are experiencing a tenant wide issue with Microsoft Copilot Chat in Outlook.

Environment:

• Microsoft 365 Business Premium
• Microsoft 365 Copilot Chat enabled
• Copilot Chat is pinned for all users via admin settings
• Copilot Chat works in other Microsoft 365 apps (e.g. Word)
• Copilot Chat is missing in Outlook Web (OWA) and Outlook Classic for all users in the tenant

Key details:

• No recent admin, policy, or licensing changes were made
• Copilot Chat does not appear in OWA, which suggests a backend or service side issue
• The behavior is consistent for all users

Questions:

• Is anyone else seeing Microsoft 365 Copilot Chat disappear from Outlook Web or Outlook Classic tenant wide?
• Has Microsoft changed the availability or scope of Copilot Chat in Outlook recently?
• Are there known dependencies or rollout changes that affect Copilot Chat visibility in Outlook specifically?

Any confirmation from other tenants or additional technical insight would be helpful.