Here is the script for the same

You can enter the date as you want, and all the records which are created before that date will be deleted: 

var gr = new GlideRecord('sys_audit_delete');
gr.addEncodedQuery("sys_created_on<javascript&colon;gs.dateGenerate('2023-02-28','00:00:00')); //Enter the date here
gr.query();

gs.info(gr.getRowCount());

while(gr.next()){

gr.deleteRecord();

}

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