Data Retention Not Working on continuous aggregates

Hello, I’m new to timescaledb
I have multiple continuous aggregates materialized from a hypertable. I have refresh policies and data retention policies on all of the aggregates, but after shutting down the database most of my data is dropped from the continuous aggregates, not following the data retention policy. The is shown below :-
Can some please help in finding out the issue with the structure of my system. How do I fix my continuous aggregates to store data for longer periods of time even when data from the hypertable is removed?

The command I used to add the retention policy was
" SELECT add_retention_policy(‘materialized_table_name’, INTERVAL ‘20 years’); "