How to replace an analog phone with IP while keeping the number?

Question

Asterisk

Available:
Panasonic KX-TDE200 connected to the city with internal numbering 1XX.
Asterix connected to KX-TDE200 via v-sipgw.
IP phone.
Analog line number 114
Task: It is
necessary to replace the old analog IP phone with the number 114 preserved
. Problem:
When assigning FWD to KX-TDE200, dialing from digital numbers does not work.
When prescribing Exten => 114.1,Dial(SIP/4484.45,r), the call stubbornly goes to the KX-TDE200.
I meet with telephony for the first time, so I can not understand everything, please tell me which way to dig.