I Can’t Get Anyone From This Company To Respond To Me - What Is My Legal Obligation For The Extra Product They Sent?

I purchased a shower soft water system for my apartment a month ago. After 12 days I hadn’t gotten a shipping notice so I emailed to inquire. A rep emailed back saying he saw an issue with tracking not updating and would look into it. A few days later he emailed saying the system hadn’t shipped, but they were about to release an updated system and they could either immediately ship the current one, or send the updated one in a few days. I agreed to wait a few days for the updated one. 5 days later it shipped, and I received it on 11/3. There were no instructions in the package and the instructions on the website are very vague, so I emailed asking for more detailed instructions. No response, but another system arrived on 11/5. No packing slip in either box and no instructions. I was not charged for this one. I emailed again in a reply to the rep who emailed me previously, and also filled out a ticket on their website. I have not gotten a response since they sent the tracking info for the first system. I don’t know if the systems are the same, so I don’t know which to install and which to return, or even how to return the extra one. If they don’t get back to me, what do I do? At this point I’m tempted to do a chargeback on the card I paid with just to get a response out of them. There is no phone number anywhere on their website or on a Google search. I even tried putting their mailing address into Google maps but got no result.

Location: I’m in NY, the company is allegedly in Wyoming.