When charging my Note 5 whether it is turned on or off will disconnect and reconnect rapidly when it is still plugged in and it will occasionally flash a warning that the Samsung issued fast charging adapter and usb cord is not compatible with the device. It will no longer fast charge so it takes several hours to charge and this causes it to take even longer. It is not the fast charging adapter and USB because I got them replaced through Samsung when a Verizon representative told me it was the cord and adapter. Which it clearly was not the issue. Any advice is appreciated since my local verizon store is of no real help.