If you’re getting a lot of spam messages from your landing page you may be tempted to use IP filtering to block the spam. Unbounce strongly recommends NOT to use IP filtering to block incoming spam.
ISPs may reuse the same IP address for numerous customers, so any filtered IP addresses may inadvertently prevent future legitimate customers from accessing your landing page, not just the spammers that you were trying to block.
If you're driving traffic to your page through an Ad or email campaign, or sharing the link directly with your visitors, we recommend hiding your pages from search engines. Hiding your pages from organic search engines lessens the chances of bot/spam traffic locating your landing page.
If you’d like to find some legitimate ways of blocking spam messages, check out these great posts on the subject matter: