Huskk review for Amp: Back in Stock & PreOrder+

I don't understand the positive reviews here. There has been many cases notifications are just not being send out to the customers. Support has confirmed this multiple times saying they are working on it. I gave them one last chance last month, just to see that two weeks after we restocked again 0 notifications were send out. This is not an app that is trustworthy with my business. I need something that does what I pay for.