To register to a DECT2060 or DECT2080 base: ) Disconnect the base AC adapter.
) Press and hold [find hs] while you reconnect the adapter. Keep pressing [find hs] until the charge LED starts to blink.
3)On the handset, press and hold [#] until the handset beeps and displays HANDSET REGISTERING.
4)When the handset finishes registering, it shows
REGISTRATION COMPLETE in the display.
What if the display shows REGISTRATION FAILED? 
Repeat the process starting with step 1.
To register to a DECT2085 or DECT2088 base:
) With the phone in standby, press [Menu/Select] on the base.
) Press [
] to move the cursor to REGISTER HANDSET and then press [Menu/Select]. HANDSET REGISTERING appears.
3)On the handset, press and hold [#] until the handset beeps and displays HANDSET REGISTERING.
4)When the handset finishes registering, it shows
REGISTRATION COMPLETE in the display.
What if the display shows REGISTRATION FAILED? 
Repeat the process starting with step 1.