Unable to log into my EX4100

I recently upgraded to fw 2.30.181.0110.2018 and now cannot login to the dashboard. I had ssh enabled so I can ssh to the device and run commands. When logging in it successfully calls /login_mgr.cgi which returns the response <?xml version="1.0" encoding="UTF-8"?>4 but the website doesnt seem to do anything with it.

I tried:
logging in using different browsers, Chrome, Firefox, Opera, Chromium
4 second reset
downgrading to older firmware 2.30.163

But none of those things actually worked. All my 12TB data is intact.

Any ideas what might be wrong?