Is there a violation of the GPL or how to behave to the author of the Open Source project LightSquid?

Greetings to the highly respected community!

I am the author of the Open Source project LightSquid - license - GPL 2
Recently found that LightSquid is used in a commercial product, and more specifically - IdecoICS version 3+.

I'm going to write to support, but tentatively decided to ask for a consultation.
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Here is a link to the page where there is a screenshot.

On the one hand, I am even glad that LightSquid is being used.
On the other hand, the lack of copyright is embarrassing, although there is a link to the site, but there is no mention of lightsquid on the page of opensource projects.

Actually the question is, how correct is the request to return to the page?

And as I understand it, they are obliged, upon request, to submit a modified version?

I am going to write to support, but previously decided to ask for advice.