SV9300 PC Port on DT800 set

[TXtac]

Customer has been experiencing issues with laptops connecting to different data ports. They narrowed it down to the NEC IP Phone that a laptop is normally connected to. The Telset is continuing to advertise the MAC address of the laptop that is connected to the pass through port even after the laptop has been undocked or unplugged.

This causes a situation where the laptop is connected to another part of the network and the phone is telling the switch that the laptop is still connected to it, so send the info to my pass-through port. This looks like the laptop is not receiving any traffic on the new port it is plugged into away from the phone.

They were able to recreate this issue to troubleshoot. In order for the MAC address to be released the NEC IP Phone needed to be rebooted. Once the laptop is connected again and removed, the MAC address is not released until the phone is rebooted again.

Has anyone seen anything like this before. System is SV9300 and sets are DT800. Do not recall the telephone "holding" the MAC address of a PC plugged in to the PC port of the telephone. Customer stated they are using a Voice VLAN and a Data VLAN.
Is there a DT800 telephone setting they are missing?