Excluding IP addresses in EZProxy

Hi 

We have a guest wifi password here but people using it can still access e-resources and we want to stop them from accessing the resources
Now I have included the IP addresses that are in the guest wifi to say ##Exclude IP .... in my config file but when I log in as a guest wifi user I can still access the resources, could anyone tell me how to exclude these IP addresses another way because it hasn't worked changing the config file

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