BLK BOX review for One Click Upsell ‑ Zipify OCU

Recently installed the app however the pop-ups don't seem to be appearing when customers click 'continue to checkout' despite being set up to do so. It bounces them straight into checkout landing page when the 'Go to Cart' button is selected skipping the shopping cart landing page? (skip to cart has been disabled but still doing this) The app seems to be very clunky and have been waiting days for a solution to my issue, had to disable the app as I don't want customers skipping the shopping cart landing page. Whilst still paying for it and lack of communication. See potential within the app if issues get sorted