Issue about did not find expected '-' indicator in "<unicode string>", line 22, column 3

[Namnt3]

I encountered below issue whenever I execute dialogue_management_model.py or train_online.py:

node = self.composer.get_single_node() File "_ruamel_yaml.pyx", line 706, in _ruamel_yaml.CParser.get_single_node (ext/_ruamel_yaml.c:9612) File "_ruamel_yaml.pyx", line 724, in _ruamel_yaml.CParser._compose_document (ext/_ruamel_yaml.c:9922) File "_ruamel_yaml.pyx", line 775, in _ruamel_yaml.CParser._compose_node (ext/_ruamel_yaml.c:10814) File "_ruamel_yaml.pyx", line 889, in _ruamel_yaml.CParser._compose_mapping_node (ext/_ruamel_yaml.c:12609) File "_ruamel_yaml.pyx", line 775, in _ruamel_yaml.CParser._compose_node (ext/_ruamel_yaml.c:10814) File "_ruamel_yaml.pyx", line 889, in _ruamel_yaml.CParser._compose_mapping_node (ext/_ruamel_yaml.c:12609) File "_ruamel_yaml.pyx", line 773, in _ruamel_yaml.CParser._compose_node (ext/_ruamel_yaml.c:10784) File "_ruamel_yaml.pyx", line 852, in _ruamel_yaml.CParser._compose_sequence_node (ext/_ruamel_yaml.c:12033) File "_ruamel_yaml.pyx", line 904, in _ruamel_yaml.CParser._parse_next_event (ext/_ruamel_yaml.c:12818) ruamel.yaml.parser.ParserError: while parsing a block collection in "", line 19, column 3 did not find expected '-' indicator in "", line 22, column 3