It is possible for two Content Filter configurations to be present on MacOS version older than 11.6. If Symantec Endpoint Protection 14.3 RU3 is installed on the device and then another MDM Content Filter Configuration Profile is pushed to the device, it can result in duplicate configurations being present in System Preferences -> Network.
An MDM Content Filter Configuration Profile being pushed to a MacOS 11.6 or older device after SEP 14.3 RU3 has been installed.
To correct a device that has duplicate Content Filter Configurations, there are two possible solutions; one through a MDM, the other locally on the device.
Only one Content Filter will remain.
Locally on device
This will leave only one Content Filter.