Hey @Ri0tdude
I agree with @Mloraditch here, sometimes old configuration can cause these type of validation errors. I would recommend checking the old version of the access control page by going to Wireless>Access control and clicking "View old version" in the top right hand corner. If you can't find the configuration in there, then I would advise reaching out to Meraki Support and they will be able to tell you the source of the problem.
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