Can this be displayed (spam by email)?

I run a Minecraft server and banned someone there because they violated the rules I had set up. For several days now I've been receiving a lot of "spam" messages via the contact form via email address - probably always from the same person. For example, the last emails said:

"Let me distribute my stuff or we will continue to spam. Or recruit your users to other servers via discord. Or we will stop when you can provide evidence (that I used xray or something similar)"

Is there any way to show that? Is there a criminal offense here? It doesn't stop and the person usually gives a nonexistent email address on the contact form.

I'm looking forward to your feedback.

To block? Is not that enough?

I wouldn't do anything. I think he'll get bored in a few days. So you give him power over you and he can dance your nose around if you allow yourself to be blackmailed

Unfortunately, this is not possible as a different email is usually given on the contact form.

Simply ignore

Is a captcha already installed on the contact form?
From a certain number of times, Google would set tasks that would at least make it slower and more complex to send requests.

Depending on how the website is set up, server-side solutions can certainly also be created (topic IP timeout)

But I don't think it will do much to show that.

If you can rule out that the person fills out the contact form automatically (bot), I would ignore it. If he doesn't hear from you, he'll stop at some point.

You can't report it, as there's no criminal offense or the like. As long as he doesn't "hack" himself back into the server, he hasn't done anything illegal here. He can write to you.