I've been locked out of EC2 RDP connection to my Windows 2019 Server instance after resetting firewall rules

I've been using a Windows_Server-2019-English-Full-Base-2020.12.09 EC2 instance in N.Virginia for a while and accidently got my firewall rules reset and it seems RDP port is closed and not accepting incoming connections anymore.

Is there anyway I could re-gain access to my instance?

I was able to disable firewall by using AWS Systems Manager.

Steps I followed

1. Log in to the Systems Manager Console
2. Verify that you are in the same Region as the impaired instance.
3. Open the AWSSupport-TroubleshootRDP document.
4. For Execution Mode, choose Simple execution.
5. For Input parameters, InstanceId, enable Show interactive instance picker.
6. Choose your Amazon EC2 instance.
7. Review the examples, then choose Execute.
8. To monitor the execution progress, for Execution status, wait for the status to change from Pending to Success. Expand Outputs to view the results. To view the output of individual steps, in Executed Steps, choose an item from Step ID.

You can also directly access by changing the region code if you have already configured Systems Manager Console.

https://console.aws.amazon.com/systems-manager/automation/execute/AWSSupport-TroubleshootRDP?region=***add-region-code-here***#documentVersion=$LATEST

If you have not setup Systems Manager you'll need to follow this Systems Manager prerequisites