Moving fiber modem to a different room.

Hi all,

i want to move my modem from upstairs to downstairs. Upstairs the fiber modem is connected via a splitter which also has Vodafone Decoder installed along with another modem for the decoder.

When i plug it in downstairs and connect it in it will not connect to the internet.

Question - do i need to get the technician in to wire the other ports in my house for fiber also? TV works fine over those ports.

Thanks