Hi,
It happens if Cloudflare picks up a false-positive firewall match. Based on the ray ID, you might be able to check what exactly triggered the firewall and make an exception to it.
Unortunately these are extremely rare and it’s never the same exact thing, it’s always something different as their WAF rules update regularly. Sometimes it’s a piece of user input text, a hexadecimal value etc.. It’s not really about the plugin version, WAF blocks requests that seem suspicious.
Another solution is to either decrease the firewall sensitivity, enable development mode or the best of the best is to add your IP address as an exception to the cloudflare firewall.