I fear that these guys may have taken your money and used it to fund other projects, and they can’t afford to refund you, or to supply you with your order. They might have made you the sacrificial lamb and burned the bridge, so that other orders can be fulfilled, in an attempt to minimize their losses. But from some comments here, it’s starting to sound like there are others led to slaughter as well.
TL;DR The moral of the story below - If you can sell everything you make AND make a living doing it, trying to grow the business by outsourcing is going to cause more headaches than it's worth. And, customers may pay less with less wait time, but the outsourced product wont be the same as if it had come from your own 2 hands.
I was in a situation over 20 years ago, before I sold my Subaru performance parts website, where I had retired from medicine due to a chronic illness. I built a cold air intake for Subaru, and I would sell and review products. At first I only sold the intakes that I produced. Later I picked up a dozen manufacturers for whom I would sell product, and they would drop ship for me. I eventually helped them with a group buy on a $2000 bolt-on turbo kit for 2000-2001 Subaru Impreza. We built the prototype kit on my car in a 3-day weekend; and while I created a 32 page page instruction manual with photos of every step of the install, they also built the jig for making more of these kits. The parts list was relatively simple. They were all set to at least double or almost triple their money, to earn back their R&D time and parts.
The manufacturer started to develop a reputation for collecting money for products but not delivering, and although my own turbo kit was a success they always ran into delays for the other 20 people. But I was never one of their victims, and knowing them personally I believed all of their excuses regarding the others, for a while.
I ended up having to help sell a lot of their items on my site that they did have in stock, to help fund their refunds; because I felt bad that I was one of their retailers who had advocated for them, while customers with their own site or other retailers got shafted. When I saw it was turning into a Ponzi scheme, where new customer’s sales were funding refunds and just enough deliveries were made to new customers to get positive feedback, I got out. It was too much stress worrying about people getting products for which I had to rely on them to supply.
At that point my orders were still being drop shipped for my customers (if I bugged them enough), while they didn't always deliver to people who ordered direct from them. It was like I was the one bridge they didn't want to burn, and could be counted on as a source for current positive reviews of their products.
I tried to sell, and then shut down my own profitable website, despite having a dozen other suppliers for all the other parts I would sell, because it was too much stress for me with my disability. I actually sold the business twice to people who also did not pay me for it, while they sold and collected money on products. My buyers had very poor customer service as well, despite having had their own business before mine. Their customers would email me personally, asking about their purchases, and I’d have to tell them that I’d sold the business several months prior after my last delivery was made.
The company causing all the issues eventually shut down, and they all went into business for themselves doing local shop work, and I don’t think they ever paid everyone back. Not sure, but it was a mess.
I was better off when I was only making and selling 50-100 intakes a month for a 50-65% markup (and nothing else), than selling $40K a month in dozens of products being drop shipped at a 15% profit margin. Like-wise, before that as a pediatrician when I was healthy, I was better off with a small medical practice and only 2 employees, than when my practice size doubled with 5 employees, and only seeing a 25% increase in income for twice the work and hours and employes! I didn't wan't to turn away new patients, but trying to find bring in a part-time doctor to a rural town didn't work the way I'd hoped. They weren't me, and that was what brought the patients to my office in the first place.