RPC Call Returns Zero Rows But Function Works as Expected

CREATE OR REPLACE FUNCTION fetch_user_details(usersid uuid)
RETURNS table(
user_detail_id bigint, 
user_id uuid, 
full_name text,
user_email text,
org_id bigint, 
org_name text
) AS
$$
BEGIN 
   RETURN QUERY
   SELECT 
   u.id, 
   u.user_id,
   u.full_name,
   u.user_email,
   o.id,
   o.org_name

   FROM user_details u
   INNER JOIN org_details o
   ON u.org_id = o.id
   WHERE u.user_id = usersid;
   END
$$
language plpgsql;