My UWB beacons doesn't work anymore


I bought 2 beacons development kit with UWB Technology and 1 sticker beacons kit (10 of them are in the kit). I made that buy last December. When I made my first tests in that month, all worked fine but I had to leave my tests because I start other activities. Recently I decided to start my development again, but now I realize that any device (smartphone, tablet, etc) aren’t able to find the signal of any of the beacons. Please, could you say me what happened? There is no a promise that the battery of the beacons is going to live at least 2 years? as you can see I bought these ones only three months ago

Please, help me to fix this, I need to move forward with my development as soon as possible.

In advance thanks.