Dealing with Fake Email Sign-ups for Your Newsletter Boost

Hey peeps, I recently accepted someone's application to boost my newsletter. Yesterday and today I got a whole lot of fake emails signing up. 0 of them verified but the money I had all are now tied up. What's the process here? Do I have to wait for a few days/weeks till the funds are freed again or is there a way for me to report this? The most unfortunate part is that the person is actually a member of this slack channel...