Recently we had a SPAM/bot "attack" on our hosted client sites on some forms without captcha. On some sites over 100 or 1000 spam posts were created (like comments, etc.).After that, we have experienced an increase in clients complaining about outgoing mails (like for example order confirmations) are going to the recipients SPAM folder. Are these two things somewhat related?We have set up SPF and DKIM records for our clients, and most of them getting 10/10 on mail-tester.com. Is there anything else we can do and/or test?

Please help.

I didn't find the right solution from the Internet.

References:-

https://www.cnet.com/forums/discussions/outgoing-mails-from-client-...

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