Bests & Worsts Reviews from Amazon

I bought this on Nov. 11, 2019. It's May 18, 2020 today. Misplaced my keys last weekend. I think I've only had to use this device a handful of times, and all the while the transmitter was carefully placed in its box in our dining room. When I went to use it, it looked like it was working. I could see a light in the transmitter, but none of the receivers made an alert. I changed the battery, and still nothing. If the seller sends me a new transmitter, I'll let you know, but as it is, sounds like I'm SOL and you may be too. It should last at least a year....don't you think? I'm past the return window, and I see nothing about warranty on their page. When I go to the seller's warranty site, there is nothing. Update on 6/11/20: I was about to junk this whole set up, but then changed the battery in one of the receivers, and it worked. Amazingly, to me, all of the receivers apparently went dead at the same time. That’s why I initially thought the problem was the transmitter. What this is telling me is the receivers are constantly running and using up their batteries even though you may never send them a signal. This makes sense to me now, but I only used two receivers and had placed batteries in all of them when they arrived. So, only put batteries in the ones you want to use, and it looks like you need to replace them every 6 months which is going to be a bit of a waste of batteries especially if you use all the receivers.