Our research survey was hit by incentive-chasing bots on 21/10 and so we region-locked the survey and added a reCAPTCHA, which worked until today, when the bots started spoofing IP addresses from our region.
As we don't publicize the direct survey link, only a page on our website (with an image and hyperlink to the survey), we tried adding a Referral URL for that page. Unfortunately, it won't allow access (either with or without a / at the end of the URL). I've reached out to Support but I'm wondering if there's anything further that I can troubleshoot. We want to keep the bots out but still be able to recruit legitimate participants.
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