The Range is much shorter than advertised

Make sure the antennas are plugged in correctly and that you did not accidentally plug in the bypass antenna into the main antenna harness, Ensure that the antennas are not touching metal.
The antennas are a sensitive component, make sure you do not tear the jacket protecting the wires, if the wire is broken and a strand is touching metal the antenna will need to be replaced
Do NOT wrap the antenna wires around a bunch of other wires, this will cause a reduction in range from interference.