Hello,
If you are using Google Chrome as your browser, the methods below might help you to solve your problem:
ERR_SSL_VERSION_OR_CIPHER_MISMATCH on Chrome: The main cause of this error is your PC not being able to establish a private connection with the website. The website is using an SSL certificate which is causing this error. An SSL certificate is used on the website which processes sensitive information such as Credit Card information or Passwords.
A secure connection cannot be established because this site uses an unsupported protocol.
Error code: ERR_SSL_VERSION_OR_CIPHER_MISMATCH
Enable SSLv3 or TLS 1.0
1.Open your Chrome Browser and type the following URL: chrome://flags
2.Hit Enter to open security settings and find Minimum SSL/TLS version supported.

3.From the drop down change it to SSLv3 and close everything.
4.Reboot your PC to save changes.
5.Now it might be possible you won’t be able to find this setting as it’s officially ended by chrome but don’t worry follow the next step if you still want to enable it.
6.In the Chrome Browser open proxy settings.

7.Now navigate to advanced tab and scroll down till you find TLS 1.0.
8.Make sure to check Use TLS 1.0, Use TLS 1.1 and Use TLS 1.2. Also, uncheck Use SSL 3.0 if checked.

9.Click Apply followed by OK and restart your PC to save changes.
Please let me know if these steps helped you.
Best regards,