I used `factor_analyzer` Python package for CFA, but matrix of factor loadings that I got contains value smaller than -1. Is a bug in the package, or maybe I misunderstood the factor loading interpretation?

factor_analyzer docs: https://pypi.org/project/factor-analyzer/

My code:

    def sem_analysis(data, group1, group2):
        scaler = StandardScaler()
        scaled_data = pd.DataFrame(scaler.fit_transform(data), columns=data.columns)
        required_data = scaled_data[group1 + group2]
        model_dict = {"F1": group1, "F2": group2}
        model_spec = ModelSpecificationParser.parse_model_specification_from_dict(required_data, model_dict)
        cfa = ConfirmatoryFactorAnalyzer(model_spec, disp=False)
        cfa.fit(required_data.values)
        return cfa.loadings_

My results:

    [[ 0.81664434  0.        ]
     [ 0.76591388  0.        ]
     [-0.84197706  0.        ]
     [ 0.         -0.27572329]
     [ 0.         -1.17491134]
     [ 0.          0.39020765]]