OK, those devices use zigbee protocol, not Wi-Fi. That matters for several different reasons.
First, the good news: they get much better battery life than Wi-Fi devices. That’s why zigbee is so popular for battery powered sensors. You will commonly get a year, sometimes even two, battery life in a zigbee sensor, where the same device using Wi-Fi might only get two or three months.
The bad news is the way they get much better battery life: they use much less power. Which means they have much less range, typically about 15 m from the hub, AND a Zigbee radio can very easily get drowned out by a nearby Wi-Fi radio. Basically the stronger your Wi-Fi is, the harder it is to get your Zigbee messages through.
There are several ways to improve the situation. The first question is do you have any other zigbee devices which are plug-ins, not battery operated? They can act as “repeaters“ and pass along messages from other zigbee Devices. This helps you cover a longer distance and sometimes can help with the interference issue as well.
What model hub are you using to control your Sensors? That will determine what additional repeaters you might be able to add.