I'm now getting the following error when trying to get the authentication methods for an account in our B2C domain, not sure when this started but i know this was working a couple of months ago..
or": {
"code": "badRequest",
"message": "{\"odata.error\":{\"Code\":\"directory_error\",\"Message\":{\"Lang\":\"en\",\"Value\":\"$expand of back links is not supported for mega tenants.\"},\"Values\":[{\"Item\":\"subCode\",\"Value\":\"error_fail\"},{\"Item\":\"requestId\",\"Value\":\"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\"},{\"Item\":\"time\",\"Value\":\"08-13-2020 10:34:05Z\"}]}}",
"innerError": {
"message": "{\"odata.error\":{\"Code\":\"directory_error\",\"Message\":{\"Lang\":\"en\",\"Value\":\"$expand of back links is not supported for mega tenants.\"},\"Values\":[{\"Item\":\"subCode\",\"Value\":\"error_fail\"},{\"Item\":\"requestId\",\"Value\":\"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\"},{\"Item\":\"time\",\"Value\":\"08-13-2020 10:34:05Z\"}]}}",
"date": "2020-08-13T10:34:05",
"request-id": "fc6f237c-c565-4b80-a825-5b82deaf36b6"