MS copilot agent authentication fails with authorization error

I am trying to configure Figma MCP in MS copilot agent using custom mcp using remore url → https://mcp.figma.com/mcp.  I get below error while creating a connection to mcp.

Failed to login. GetDynamicClientRegistrationResultAsync failed. Status Code: Forbidden, Response: Forbidden

can someone experience such issue and fixed it? Please note that same mcp with remote url works well in vscode.