Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Costly Dissappointment

I am using it as a stand alone in a home office. Featurewise it is ideal for this purpose. However, I have lost power in the building a few times this year and the internal battery backup has never retained the program settings - which are extensive and confusing. I agree with others, the most annoying anomoly is the failure to drop an incoming call to voicemail while you are on another call. (Your caller hears constant ringing.) I cannot tell you how many times my customers have said they tried to reach me but my phone was broken.(...)