Cannot connect to openemr hosted on amazon AWS

Situation
Describe your problem here
I installed Openemr on amazon aws, and it was ok for 6 months. Then suddenly I cannot access it from my browser or even copying and pasting the public DNS. I asked amazon support and they said everything is ok on their side and it seems to be an Openemr problem and even directed me to this site. Anything helps, thanks!
OpenEMR Version
I’m using OpenEMR version
Express edition 50051
Browser:
I’m using:
Safari, chrome
Operating System
I’m using:
mac os x
Logs
Did you check the logs? Was there anything pertinent in them? Paste them here (surround with three backticks (```) for readability

hi @David_Cai openEMR Cloud Express Plus - Hipaa Eligible?