Local Backup Doesn't Respect Retain Policy

Provider: Digital Ocean

System: Centos 7.6

OLS or Enterprise?
OLS

Installing from official server or mirror server?
Mirror

Replace JS/CSS files to JS Delivr?
yes

Install Memcached extension for PHP?
yes

Install LiteSpeed Memcached?
yes

Install Memcached?
yes

Install Redis extension for PHP?
yes

Install Redis?
yes

Problem :
I set up S3 backup with 3 days retain policy but the local copy of the backup doesn’t get deleted even after 3 days. In fact, it never gets deleted. I have to delete them manaully.

Me too, I use Amazon S3