Cause
The OAuth authentication of the destination must give scope or audience.
What to do
Give at least one.
application/problem+json
{
"type": "https://masnet.com/developers/errors/missing_scope_or_audience",
"title": "Missing scope or audience",
"status": 400,
"detail": "...",
"code": "missing_scope_or_audience",
"correlation_id": "..."
}