When you installed Qlik Sense, what was the server name configured? Did you change keeping only the hostname or have fqdn (servername.domain/servername.localhost)?
Ever installation, to solve and ensure the correct operacional, I did a installation changing this box to keep only the servername. After the server installed, you only need access https://servername, a few minutes after the services were started.
If you problem still happening, try uninstall and install like I mentioned.