Why would you need to send body with delete?
The API reference mentions it https://www.traccar.org/api-reference/#operation--permissions-delete. Do I miss anything?
You are right. Unlinking does require object. I don't think there's any way around it.
I'm not sure why you don't support to send the parameters as query strings, at least for DELETE method.
I'm working on a .NET Core client that uses HttpClient to unlink device and geofence. But HttpClient doesn't allow to send data in body with DELETE method.
Does Traccar support X-HTTP-Method-Override? For more information about X-HTTP-Method-Override, you can find here https://www.hanselman.com/blog/HTTPPUTOrDELETENotAllowedUseXHTTPMethodOverrideForYourRESTServiceWithASPNETWebAPI.aspx
Thank you