Landline phones are sometimes told that they are turned off during a call. There are several reasons for this:
1, the phone number is displayed as a landline number, but is actually using a mobile phone call. Now there are a lot of phones, the number is in the form of a fixed line, in fact, it is a card type of mobile phone, can be used as a mobile phone card, Unicom, telecom have this kind of number, if you call is this kind of number will appear shutdown phenomenon, because this card in addition to the number is in the form of a fixed line and the function of the mobile phone number is the same.
2, the call is indeed a landline, he uses a wireless fixed phone, but the landline has no power or poor signal to \"the phone you dialed has been turned off\" to reply. The landline number dialed has been transferred to the phone, and the phone will be turned off when the phone is turned off.
3, some landlines have a function key, that is, \"VIP\/do not disturb\" function key, if you call this landline when you start the do not disturb mode, it is likely to have a shutdown reply.