How can I talk to support?

To address your concerns about unexpected AWS charges and billing issues, the best course of action is to contact AWS Support directly. Here's how you can do that:

1. Sign in to your AWS Management Console.
2. Navigate to the Support Center.
3. Open a new case under the "Account and billing" category.

This type of inquiry can be made free of charge, even for customers without a paid support plan. When creating your case, provide detailed information about your situation, including the unexpected charge and your concerns about the free tier usage.

Regarding the 750 free hours, this is typically part of the AWS Free Tier offer, which provides a certain amount of free usage for specific services within the first 12 months of account creation. However, charges can still occur if you exceed the free tier limits or use services not covered by the free tier.

As for the pending transaction where money has already been deducted, this could be due to the way your bank processes transactions. Sometimes, banks may place a hold on funds for a pending charge before it's fully processed.

When you contact AWS Support, be sure to ask for clarification on:

1. A breakdown of the charges you've incurred
2. An explanation of how you may have exceeded the free tier limits
3. The status of the transaction and why it's showing as pending

Remember to review your AWS usage and billing details in the AWS Billing Console to get more information about your charges before contacting support. This will help you have a more informed discussion with the support team.
Sources
I need help with billing. | AWS re:Post
Billing Complain | AWS re:Post
Why was I charged on AWS free tier period? | AWS re:Post
AWS payment issue | AWS re:Post

When you talk about 750 hours I'm going to assume you're using EC2 instances, as it's where most people start with AWS.

EC2 isn't a free service. When your account is in its first year you can provision some low-spec'ed instances within Free Tier https://aws.amazon.com/free

750 hours per month of Linux, RHEL, or SLES t2.micro or t3.micro* instance dependent on region

750 hours per month of Windows t2.micro or t3.micro* instance dependent on region

750 hours per month of public IPv4 address regardless of instance type

All other instance types are always chargeable.

Which instance type did you use?

if you provisioned a NAT gateway then that is going to be chargeable too https://docs.aws.amazon.com/vpc/latest/userguide/nat-gateway-pricing.html

Advice on how to stay within Free Tier is at https://repost.aws/knowledge-center/free-tier-charges

After reviewing all of this, if you feel you have been billed for something unfairly your best course of action is to log a billing support case https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/billing-get-answers.html#billing-support