You need to do a mid-point update to 2.2.17xx first before you can go higher, and you also need to make sure that nothing not even a charge cord is plugged into the second USB.
You can follow this link:
You need to do a mid-point update to 2.2.17xx first before you can go higher, and you also need to make sure that nothing not even a charge cord is plugged into the second USB.
You can follow this link: