The unit freezing only on very hot days may mean airflow is marginal or refrigerant is low

https://winterhavenhvacrepair564.evergrovio.com/posts/5-questions-to-ask-a-top-rated-air-conditioning-company-before-booking

The unit freezing only on very hot days may mean airflow is marginal or refrigerant is low. Shut it off to thaw and have a technician inspect pressures and filters.