Yotpo: Email Marketing & SMS

We have been wondering what is going on with this app for the last couple of months. We have spent hundreds only to have every single campaign fail. We have a list of a few thousand, 49 emails are delivered yet we are charged for the several thousand. Since Yotpo has taken this over it's not worked at all. Will be asking for a refund from Shopify. Best to not install. It's no longer working as it has for the last several years. Too bad...this WAS an affordable option. It's now just costing us marketing $$ with 0 return.