I accidentally unsubscribed an SNS topic. When I am trying to delete this subscription, I got below error:

Couldn't delete subscription.Error code: InvalidParameter - Error message: Invalid parameter: SubscriptionArn Reason: An ARN must have at least 6 elements, not 1

To recover this subscription, I executed below CLI command:

aws sns subscribe --topic-arn <SNS_TOPIC_ARN> --protocol email --notification-endpoint <EMAIL_ID> --region <AWS_REGION>

Then I was able to receive the email “AWS Notification – Subscription Confirmation”. After clicking “Confirm Subscription”, the subscription was successfully seen in SNS console.