r/Dataverse

I have created 2 tables in dataverse. Then create a many-to-many relationship on one of the table. By clicking the relationship it provide me the relationship name and the table name.

I tried to call the api to get the details of middle table. But all I got is

{"code":"9004010A","message":"An unexpected error occurred while processing the request"}

I tried to find a sample code or tutorial online but failed to do so. Maybe there are not many people use dataverse with api now? I have asked the opinion from AI and all failed. Please give me some hints.