HTTP 506 Variant Also Negotiates indicates a server configuration error where the chosen variant resource is itself configured to engage in content negotiation, creating a circular reference that cannot be resolved.
The server's transparent content negotiation configuration has a circular reference — a variant points back to the negotiation process.
Review the server's content negotiation rules and ensure variant resources do not themselves participate in negotiation.
Use a direct URL or specific Accept headers to bypass the negotiation loop.