Which estimator to use
Depending on the way your items are measured or how they are distributed, you may want to use another estimator. You can check the normality assumption in the "Descriptives" tab.
Gana and Broc (2019) recommend the following regarding the main estimators:

Data type and normality assumption | Recommended estimator
Continuous data |
Approximately normal distribution | ML
Violation of normality assumption | ML (in case of moderate violation) MLM, MLR
Ordinal/Categorical data |
Approximately normal distribution | ML (if at least 6 response categories) MLM, MLR (if at least 4 response categories) WLSMV (binary response or 3 response categories)
Violation of normality assumption | ML (if at least 6 response categories) MLM, MLR (if at least 4 response categories) WLSMV (in case of severe violation)

References
Gana, K., & Broc, G. (2019). Structural equation modeling with lavaan. John Wiley & Sons.