Any chance the latency on the internet connection is high, and the downlink packets arrive at your gateway too late? (Using a serial port monitor, I got one LORA: TXPKT failed, too late! today, but that’s often caused by problems in the backend, not in my connection.) Is the gateway registered to the router closest to you? (So, ttn-router-eu for France.)
Meanwhile your gateway has forwarded 112,350 112,439 112,455 112,475 uplinks, though those might not all have been sent by your own node. Still then, if TTN tells a gateway to send a downlink, it should indeed do so.