Incorrect updating time reported for a project

I have a gitlab account for over 3 years. I don’t access it too much, but I have a lot of my old projects in it - all PRIVATE!
I haven’t access it in at least 3 months (if not more…). Today, while opening my gitlab.com account on web, I see that one project reports “updated 3 days ago” !?.. but 100% sure I did not work on that project in the last 2 years!
In fact, if I click on it, it confirms that my last activity on that project is 2 years ago.

So, how come the main page of gitlab.com (the one that lists all projects) says “updated 3 days ago”? Is it a bug with gitlab.com or what else could be the reason?

Thanks,

DC