Unable to create _opendistro index in elasticsearch

‘{“error”:{“root_cause”:[{“type”:“invalid_index_name_exception”,“reason”:"Invalid index name [opendistro], must not start with '’, ‘-’, or ‘+’",“index_uuid”:“na”,“index”:"_opendistro"}],“type”:“invalid_index_name_exception”,“reason”:“Invalid index name [opendistro], must not start with '’, ‘-’, or ‘+’”,“index_uuid”:“na”,“index”:"_opendistro"},“status”:400}’,
toString: [Function],
toJSON: [Function] }

Need help!!!

According to error message index name cannot start with “_”