My AWS Amplify uses almost 5GB. I don't know why

I got an email.

Your AWS account 5********* has exceeded 85% of the usage limit for one or more AWS Free Tier-eligible services for the month of June.

Product AWS Free Tier Usage as of 06/02/2022 Usage Limit AWS Free Tier Usage Limit

AWSAmplify 4.74107138 GigaBytes 5 GigaBytes Free tier - storage

However, my amplify hosting size is less than 50MB. I don't know where the storage usage came.

I found a same question, https://repost.aws/questions/QUWRU08gzgRP6vNwFJPCXJDA/how-to-reduce-aws-amplify-data-storage

How can I solve this problem?

Thank you