我再也无法连接到我的aws实例了

I've been running tomcat on my Amazon EC2 instance for a few weeks just fine but all of a sudden, I became unable to connect to it. When I use putty I can connect to it fine but when I try to connect with my browser by using ip:8080 , I can't connect anymore. I've tried restarting the instance (and of course, adjusting my input ip accordingly), restarting the tomcat server within the instance, and checking the security groups. Nothing seems to work. I have no idea why it stopped working out of the blue. How should I proceed?I've been running tomcat on my Amazon EC2 insta