What are effective ways to protect forms from manual spam?

Question

Fight against spam

Hello!

The site used to receive more than 20 spam messages per day.
Then we added a text field and added styles to it and did a check for the emptiness of this field. Spam has decreased, but it still has not disappeared. Now about 5-10 spam emails per day come from the site. And they look like manual spam. So, tell me please, good ways to protect against manual spam. ps the website has recaptcha v3 position: absolute; opaicyt: 0

Answer 1

only a trained spam filter on the server can help from manual input.
for example, spamassassin, if messages fall on soap.