You should De-Register your Handset, and then Re-Register it to your base. Here are the instructions:Handset Registration
1. If your handset is purchased as part of a system, it has been pre-registered with the base station at the factory.
2. If the Handset ID reads "00," that means it is a new handset or the ID has been erased. You need to register the handset with the base station. In certain situations, you may want to change
a handset's ID. For example, you want to change a particular handset from a user to an administrator (ID 10 or 11), or vice versa. Or in some rare occasions, you find another handset
having the same Handset ID.Registration:
a. Press MENU-6 to enter the registration mode
b. Press and hold the base's Registration (REG) button for 2 seconds until the L1, L2, L3, and L4 LED come on.
c. Press handset key "1", this completes the registration process. The base station will assign a handset ID between 10 and 99. The assigned ID will be displayed on the handset LCD, indicating successful registration.
d. Repeat above steps for all additional handsets.
e. The first two handsets registered will be given ID 10 and 11, which gives them administrator privileges.De-registration:
a. You can de-register a handset from a base. Deregistration will reset the Handset ID to 00, erase the system security code, and free up the old ID for future registration.
b. After deregistration, the handset will not be able to use the base to make or receive phone calls, nor can it intercom other handsets.
c. Press handset MENU (Right) soft key.
d. Press the handset number key "6", this will enter the handset registration menu.
e. Press and hold the base's REG button for 2 seconds until L1, L2, L3, and L4 LED come on.
f. Press the handset number key "2", this completes the deregistration process. Upon successful de-registration, the handset will show ID "00".
NOTE: The base has a 30 second registration timeout starting from pressing the REG button. The handset has a 12 second registration timeout starting from the registration or deregistration option has been selected. The base and handset will automatically exit registration mode after timeout.
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