Uhm I had a similar issue yesterday
the static html wasn´t working, what I did erased the website and create again
and then get an ssl certificate (which may be tricky for you since you have no domain (maybe a self signed certificate?)
the way to access it should be it should be 192.168.1.20:80
there it should be working
seems like the new Nginx or aapanel require by default to connect through SSL
at least it was my error
it gave me error 404, website not reachable, server took too long to respond etc
and it all got fixed by deleting the website creating a new one and later adding a certificate , then force ssl
and voalá!!! working
hope it helps
