Drone hacking not possible after moving the drone.
After moving the drone to a new portal it isn't possible to hack it, I recoeve the message that it has been burn't out.
I can get around this by closing the app, restarting it and when I go into drone net the drone is at the portal I moved it to and I can hack it.
There is another option and that is o move the drone, exit drone net, enter drone net again, move the drone again (because it is at the previous location) and then I can hack it succesfully.
I found out this bug can also be used as a feature that allows me to move and hack with the drone twice every hour (or twice every 15 minutes during the current event).