My end device console in TTN(dragino lora shield with DHT11 sensor) is not receiving uplinks although the gateway is receiving uplinks. I used ABP. The NWKSKEY, APPSKEY and device address in my code are correct(msb format and device addr in uint32_t format).
Try switching to OTAA and see how it performs then would be 1st step - assuming you have everying else configured corrrectly, Keys, MSB/LSB, freq plan etc. Also check what spread of channels the received messages at GW are seen on. Which firmware stack are you using? (source link). Signal strength high but not a concern at this point (another meter or two of seperation might be useful). Can you post configs from server and device and any serial o/p from device?
Also change (reduce!!!) uplink rate - just letting it run free hammering uplinks wont solve problem, perhaps add a push to send button then you can see a message in isolation… with such a strong signal and good SNR suprised to see missing fcounts so clearly something else is wrong…
At what frequency are the uplinks received by the gateway? And which frequencies have been configured for the end device?