During a debug session, whilst your target is executing , the debug tools will poll the target to determine whether it has halted on a breakpoint or event. A "16: Target error from status-poll: Ee(02). Not connected to emulator" error is returned whenever the debug tools cannot get the present target state. In this case, the debug connection to your MCU is considered offline.
Some of the things that could cause this error include:
If you are connecting to the target using a Red Probe+ (but NOT using an LPC-Link), then in the Project Debug Configuration, you can specify a reduced wire speed (i.e. "Maximum wire speed). The default is typically 3 MHz, or 3000 KHz. Setting this value to a lower number, such as 1000 KHz (1 MHz), can sometimes improve matters - though this depends on the actual cause of the status-poll error.