Universal SSL is essential for your website to work with HTTPS when you don’t have a valid SSL certificate yet. In the majority of cases, it’s recommended to keep Universal SSL enabled. However, sometimes you may need to restart the Universal SSL to solve some certificate-related issues.
If you have enabled Cloudflare for your domain, you can manage Universal SSL from the Cloudflare Dashboard:
Log into Cloudflare and click on the domain in question. Then, in the left menu, choose SSL/TLS → Edge Certificates:
Scroll down to the Disable Universal SSL section and click on Disable Universal SSL:
Wait for a minute and then enable it once again by clicking on Enable Universal SSL:
That's it! Your Universal SSL should be working correctly.
Additional Resources