For ABP you don’t need to program new keys every time you reset them. But you should reset the counters in TTN Console (or using the command line ttnctl) at the same time you reset the ABP device. (Or disable the security, but like linked-to in an earlier answer: that might need handling in the device as well, for the downlink counters.)
I think key is: do you see the uplinks in the gateway traffic?