This is the reason why I always buy name brand devices when it comes to smart devices. Any IOT device needs the backing of a financially strong company to keep going.
I had two things that went dark on me in the past few years.
First was the Pebble Smartwatch. It began as a Kickstarter. It was cool to have one of the first smart watches on the market before Apple and everybody else. But eventually Fitbit bought out Pebble and killed the product and the company. I don't think it was ever their intention to continue the Pebble brand or product line although their official statement was to use Pebble's technology.
The other one was a cheapo smart plug made by Buzzi Blackloud. They turned off their servers in 2019. The smart plugs are just bricks now. I'm surprised they even lasted till 2019.