Objects gets deleted manually from S3 bucket from AWS console.
Issue:
S3 backup objects in a bucket get
deleted manually directly from the AWS account.
For example, a user logs into AWS and deletes items stored in the bucket manually.
Solution:
This is not a supported method of deleting backups. You will need to create new full backup of any resources that were being backed up to that bucket.
To force a Full copy follow the steps below.
1. Open the policy
2. Go to backup targets -> select the instance
3. check the below box to force a single full backup to S3: