Abnormal Billing for the Free Resources

There are a few potential reasons why you might be seeing charges for RDS and VPC resources even while on the free tier:

1. For RDS:

   • Make sure you're using an eligible instance type (db.t3.micro or db.t4g.micro) in a Single-AZ configuration.
   • Ensure you're using a supported database engine (MySQL, MariaDB, PostgreSQL, or SQL Server Express Edition).
   • Check that your storage doesn't exceed 20GB.
   • Remember that the free tier is limited to 750 hours per month.

2. For VPC:

   • While VPC itself is generally free, certain associated resources may incur charges.
   • If you have a public IPv4 address attached to your RDS instance or any other resource, this could result in VPC-related charges.

3. General considerations:

   • The AWS Free Tier typically lasts for 12 months from account creation. Verify that your account is still within this period.
   • The estimated charges shown when creating resources often reflect what you'd pay after the free tier expires, but you shouldn't actually be billed if you're within the free tier limits.

To investigate further:

• Review your detailed billing statement to identify specific services and usage causing the charges.
• Check your free tier usage status in the AWS Billing Console to ensure you haven't exceeded any limits.
• If you believe you've been charged incorrectly, you can contact AWS Support to open a billing support case for clarification or potential adjustments.

Remember, it's crucial to monitor your usage carefully, even with free tier resources, to avoid unexpected charges.
Sources
DB instance billing for Amazon RDS - Amazon Relational Database Service
Why is Free tier RDS Sql single instance usage showing monthly estimated bill?? | AWS re:Post
Charges on Free Tier Account | AWS re:Post
Understanding unexpected charges - AWS Billing

Could you also refer to this :- https://repost.aws/questions/QUzcVoqSA2RsqhgtyhX-DPEg/charges-on-aws-rds-and-vpc-despite-free-trial-for-a-year