Event Triggers unable to capture the DDL script executed

We are using event triggers to capture the DDL changes in a postgres database. However, we are unable to get the column information & the actual DDL script executed, while a table is altered. 

Also, in the postgres documentation for pg_event_trigger_ddl_commands ()- it is mentioned as below.

pg_ddl_command

A complete representation of the command, in internal format. This cannot be output directly, but it can be passed to other functions to obtain different pieces of information about the command.