Can a wireless usb modem by interfered with a power line above it?

Hardware
1

I need help
I am configuring a wireless air quality sensor. I use a wireless usb modem and Alpa software to scan for this sensor. I am able to find it when I am in one place but when I move further away, it is no longer visible in Alpha software. The place where I try to test it has a power line above it in the air. Could this cause a disturbance with the electromagnetic field?
How is this possible?

2
  1. what the radio module frequency
  2. do you have antenna connected
  3. are the antenna pointing towards the sky
3
  1. I am using the 868 MHz modules.
  2. The antenna is connected.
  3. The antenna is pointing towards the sky.
4

what is the distance between sensor and modem ?

5

They are standing next to each other. But they are not too close.

6

I will recommend keeping them at least 5 ft apart.
when you say, " if I move the sensor modem far away you don’t get data" how far away?

7

When I try to scan for sensors in Alpha software when I am under the powerlines it does not find them. But when I move away from the powerlines it scans just fine.