I have two problems and I have not idea how to fix it. Problem is because these months some bot registered thousands of accounts, and subcribed to newsletter.
We did not noticed that because we did not used Newsletter function, and at this moment checkout on this site is disabled.
1. Registered customers. I can recognize what is bot job, because of Chinese letters. Something like this. domain is qq.com
Problem is because when I select more then 50 of those records and delete it, I'm getting Timeout error. And if i do that 20 by 20, it will take too many time for 4-5000 Customers .
I tried to find how to make SQL query for deleting it with condition where e-mail is *@qq.com, but I did not find solution.
Can you help me with advise how to delete all customers?
2. Problem is about Subscribers.
There is very difficult to recognize bot users.
Is there any option for unsubscribe them all and send them again subscribe mail?
Of course, my plan is to enable mail confirmation for users registration, and mail confirmation about subscription.
Also I will enable captcha
But how to fix this things now?