HI @darkpanda08
Can you share which board are you using RAK4600 LPWAN Module,EVB or Breakout Board ?
Check if you are powering the module not only from the J-link.
Hi @darkpanda08
Check your connection with the FTDI module you are using and your pin order too.
You also can check the J-link device you are using it may be causing trouble.
Just flashed RAK4600 Breakout Module and RAK4600 LPWAN Module everything went fine.
Try to power it by another source.