Hi,
Thank you for posting your query. According to your description, it seems that you have trouble getting through RDP connection. Here are some hints for you.
General Remote Desktop connection troubleshooting
https://learn.microsoft.com/en-us/windows-server/remote/remote-desktop-services/troubleshoot/rdp-error-general-troubleshooting
Additionally, you may try to update your AWS EC2 and check whether the same problem occure.
Best Regards,
Grace
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