This error occurs when there is some misconfiguration between SSL and Cloudflare. No worries, it's easy to fix.
Step 1 - Disable Universal SSL
After disabling it, wait a few minutes for changes to take effect, and enable Universal SSL again. So, in the end, you will see the same window as before:
Step 2 - Clear cache
Now you only need to make sure that you are checking the latest version of your website. For that, you just need to purge Cloudflare cache.
Once it's done, give it a few minutes and your site should be back up and working in no time! 😊
If you're not using Cloudflare or the issue persists, you can find more information in the following tutorial: How to Fix ERR_SSL_VERSION_OR_CIPHER_MISMATCH