The RN2XX3 devices are Class A LoRaWAN devices, these can only listen a short period of time after sending a message first.
The firmware supports NON LoRaWAN features, like point-to-point LoRa, hereby you can set the device into listening mode. But only at a single channel. I don't have much experience with this feature, since it's not in the official LoRaWAN specs.
I recommend you buy a proper gateway and have the data stored there.
Here is a nice overview of available gateways: