FreePBX CID Passthrough

Hello All,

I have a FreePBX running
PBX Firmware:10.13.66-17
PBX Service Pack:

The SIP registrations on the FreePBX are
Switchvox–>(pjsip)Registers To–>>FreePBX<<–Registers To(pjsip)<–Digium ISDN Gateway

FreePBX is only used as a pass-through server

FreePBX has 2 X Incoming routes

DID CID Description Destination
_54xx Any Switchvox_to_Gateway Trunks: Gateway (pjsip)
_55xx Any Gateway_To_Switchvox Trunks: switchvox (pjsip)

5401 is a SIP endpoint on the ISDN Gateway
5520 is a SIP endpoint on the Switchvox

When 5401 calls 5520 FreePBX sees the INVITE which has the FROM and the TO fields and passes the call through without issues
When 5520 calls 5401 if the Switchvox sends the Caller ID " FROM " as [email protected] FreePBX does not process the call, i.e there are no invites sent out,However when the CID is hidden as " anonymous" by disabling CID on the Switchvox trunk where [email protected], FreePBX routes the call through to 5401 without issues and 5401 sees the caller as ANONYMOUS.
So basically FreePBX routes through when the CID is anonymous and doesnt route when the CID is a number.

I have tried to set the destination on the Inbound Route to SET CID and then passthrough to the trunk and have had no luck.
I have tried to modify the incoming route to DID= " _54XX" and CID = “_55xx” and have had no luck.
I have changed the registration method(Peer) between FreePBX and Switchvox and have had no luck
I am not sure if I can use an Outgoing route in this Scenario,If Yes, How ?

Please help !