How to improve RAK7289CV2 scope?

Hello,

Here’s my situation:

I have a gateway RAK7289 Edge pro (RAK7289CV2) and a RAK4630 card (with the antenna mounting plate for BLE+LoRa, included in this kit). On the gateway, I placed two antennas like this one.

The problem is that, with the tests I’ve carried out over the last few days, I’m having trouble getting exchanges beyond 700 m. I have a case where I can communicate at a distance of 1200 m, but only at a specific location (it is high up on a sort of mound).

I placed the gateway outside, with the antennas held vertically otherwise I don’t even reach 200 m range. I’ve tried increasing the TX power to the maximum value (7 for the device, 27 for the gateway) but I don’t get any significant difference in range.

Is the equipment I have sufficient to cover a 2 km radius? If so, how can I improve transmission to achieve this coverage?