Thanks for writing is!
Please check this for a possible fix.
Also Please check this steps.
1. If you're using a CDN, please clear the CDN's cache and disable optimization services. For the CloudFlare please follow the steps below: https://xthemetips.com/using-cloudflare-rocket-loader-with-x-pro-and-x5/928/
3. Reset your htaccess file by renaming it to .htaccess-bak. Then in WP Admin Menu, go to Settings > Permalinks and just click the Save Changes button.
hope this helps!