If you get an ERR_SSL_PROTOCOL_ERROR error when opening your website, it is most likely related to an issue with your SSL certificate. If you don't have an SSL certificate installed yet, you can easily install it for free from hPanel.
If you do have an SSL certificate installed and are still getting this error, you can try the following:
Clear your browser history and cache, or check the website through incognito mode
Temporarily disable antivirus and firewall programs on your device
Use SSL Checker to check if your SSL certificate is valid. If the tool shows that your SSL is not valid, contact your current SSL provider. If you are using our Lifetime SSL, get in touch with us, and we will check it for you!
Use the DNS Checker tool to confirm that your domain is pointing to the correct nameservers
You can also check the following video Tutorial for more alternatives: