WTF Notebooks review for Fomo: Social Proof Sales Popup

Not happy. We are on the "$49 per month" plan and have intentionally set a limit of 239,000 impressions in the app settings to guard against overages. Assuming any overage charges are retrospctive, December 2020 charges by FOMO were $129 (total of 317k impressions for Nov-Dec), January charges were $70 (total of 214K impressions for Dec-Jan). Why did Nov-Dec go so much above our cap (317k), and how is charging MORE than the next tier even justifiable? (1.2mil impressions for $99 vs. an ACTUAL charge of $129). Why were we charged overage fees in Dec-Jan with a LESS reported impressions than our cap (214k)? Shouldn't this only be $49 because it was less than 240k impressions? Of note are mysterious items in our bill called "Usage Fees"(?)... so now I'm going to have to go through the fine print and figure out what these are and why FOMO is charging us so much. $200 over two months for a product which we assumed would cost half that. Feel like FOMO writes their own checks. Disappointed.