Please include the following information when submitting a bug report:

• LoPy L01
• 1.19.0.b3

(sysname='LoPy', nodename='LoPy', release='1.19.0.b3', version='v1.9.4-44b21d6 on 2018-07-01', machine='LoPy with ESP32', lorawan='1.0.2')

• Exact steps to cause this issue
  1. esptool -X -c esp32 --tx-break -b 921600 --after no_reset -p COM3 erase_flash
  2. from network import LoRa
  3. lora = LoRa(mode=LoRa.LORA, region=LoRa.AU915)
  4. lora.mac()
• What you expected
  • To see aa-bb-cc-dd-lo-ra-ma-cc
• What happened instead
  • "And its gone", ff-ff-ff-ff-ff-ff-ff-ff

I have discovered the hard way that the LoRa MAC is not stored in some fuses but in flash, I've deleted it. Is there anyway to recover the former LoRa MAC address of this device? If I provide you with the WiFi MAC do you have the LoRa MAC available? The unique id is 24-0a-c4-0a-ab-c0

Cheers.
Josh.