The phone book from the Gigaset 5455 SIM cannot be transferred directly to the Gigaset Comfort 550A DUO via SIM card, as the Comfort 550A DUO is an analogue landline telephone and does not have a SIM card function.

Phone book entries are usually transferred between Gigaset phones using the "Send list" function in the phone book menu if both handsets are registered to the same base station. To do this, select an entry in the phonebook, press "Options" and then "Send list" to send the entries to another handset. However, this only works if both devices are compatible and are registered to the same base station.

As the Gigaset 5455 SIM is a handset with SIM card function and the Comfort 550A DUO is an analogue landline telephone, it is not possible to transfer the phone book entries directly between these devices. Alternatively, you can export contacts using PC software such as "gTool" and then transfer them manually to the other phone, provided the phone supports this.

To summarise: It is not possible to transfer the phone book directly from the Gigaset 5455 SIM to the Comfort 550A DUO using the telephone function. Contacts must be transferred manually or exported and imported via PC software.