Have a 3300 MXe Ver. 8.0.9.22 the keysets are 5330s. We have programmed a make busy button for the agents in the ACD H/Gs. the COS is set to have them in busy mode when first logging in then use the make busy key to unbusy themselves. Sporadically this button doesn't work. When going into Multiline set key it shows the correct label and "Not Assigned" in line type. This happen while they are on a call, overnight, out to lunch, ect. Open for any thoughts.