Because an analog phone has two feature buttons (0 and 1), when configuring the hotline feature, it is important to define which button is to be set as the hotline key. For example, hotline call to number xxx-xxxa should be set to key 0 and hotline call to number xxx-xxxb should be set to key 1, where xxx-xxxa and xxx-xxxb are different destination numbers.

Also, when the phone is in an off-hook state, set hotline key to 0 (line-0). However, when the phone is in a call (line-0), set hotline key to 1 and press Flash key one time to either transfer the current call or to connect to a conference call.