If you’re looking for a way to cut down on these, you might want to try using a contact form on your website to conceal your email address. It’ll still forward submissions to your email but without revealing your address. Most decent web hosts with site editor tools will provide that kind of functionality without requiring any coding/development knowledge. That said, your existing address is pretty much toast at this point so you’ll need a new one regardless.

If these messages are being sent to a domain contact via public registration info, well, there’s your problem. Those contacts should either be burner email addresses or be hidden behind private domain registration.