I'm getting an unusual hike on subscribers but my analytics didn't register. What could be happening?

I paused a project like 1 month ago, and when I returned to cancel the email service I noticed I've been getting like 50 subscribers in the last 7 days (It's like they knew about it and wanted me to change my mind).

I have Heap, GA, and Fullstory connected, but the user subscriptions are not registered there, and there aren't any sessions recorded as well (In FullStory). Mailerlite subscriptions and the Zapier task log are the only ones showing a lot of subscriptions.

What could be happening? Are they using anything to hide their privacy? Or is it on my analytics side?

Thanks in advance guys!