Multiple Uplinks received at gateway end

One of the nodes I’m using only sends 1 uplink at a time but I see 3 Data Uplink on Gateway’s Live Lorawan Frames.
Any reason why this would happen?

They have different LoRaSNR & RSSI but same mic

What about the frequencies on which the frames are received? When a device is really close to the gateway (which you should avoid), it is not uncommon that it is received more than once.