Spamming affiliate registrations by Bots

We installed the free YIHT Affiliate plugin a week ago ago test it before purchasing the PRO version. Since than we noticed we’re getting a lot of bot affiliate registrations. Up to date more 900 registrations and sometimes more than 100 per day. Our affiliate form has a RECAPTCHA and so the users have to solve it before registration. The bots are solving it and registering anyway. I asked around and even the PRO version of the YIHT Affiliates has the same issue. The bots are coming mainly from @myagkie-paneli11.ru, @rudiplomust.com, @xruma.store, @best-lip-filler.com. Most of them from @rudiplomust.com. There is no way to block certain email accounts from registering affiliates.

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