(please specify the URL of the site on which you are experiencing the problem)
The webpage at https://sv1.scriptinstall.rocks:2083/login/?user=if0_41334935&pass=sidecutter21 might be temporarily down or it may have moved permanently to a new web address.
ERR_TUNNEL_CONNECTION_FAILED)
(other information and details relevant to your question)
As a kind notice you have shared your password in your topic
First of all, be very careful when sharing URLs on the forum! Carefully check them to make sure that they do not contain any data you don’t want to share. In this case, you accidentally shared your hosting account username and password, which would allow anyone go gain full access to your hosting account.
To fix this, I have reset your hosting account password. You can see it in the client area. Feel free to change it, but do not reuse your old password, because it has now been compromised.
As for the specific issue, I think that this is caused by the cPanel port not being accessible on your network. As you can tell from the :2083 part in the URL, Softaculous does not use standard web ports. This may not work correctly if you are using a web proxy that does not support this.
You can verify whether this is the case by checking another host that uses this port, like the official cPanel demo. If you get the same error there, you can be sure that it’s the port issue I referred to. If you see a login page, it means it’s something else (don’t try to login, it’s a generic demo, we’re just trying to check if you can reach it at all).