Noob - Setting up Axioma Qalcosonic E3 Heat Monitor device - all preconfigured!

So what does the gateway’s Traffic page show in TTN Console? Sometimes it shows nothing, or only shows uplinks but no downlinks, all due to being unreliable. So, until you see some Traffic you may need to rely on what the Device’s Status and its Data page show you:

But if the gateway’s Traffic does show traffic, then that helps a lot: if it shows a Join Request (orange icon) while the device’s Status or DevAddr do not change, then you know that the configuration is wrong. You can validate the AppEUI and DevEUI as sent by the device from the Traffic page, so if those are okay then only the AppKey may be wrong. If it shows no Join Request, then the device is probably not sending one, or is out of reach. If it shows the Join Request and a Join Accept, then the device probably has not received that accept downlink.