VMX Locator - forwarding SIP Trunk account number instead of Caller ID?

Hello, I have just setup VMX locator on our FreePBX_13 system and set “Press 1” to divert to a mobile phone number.

The call successfully connects to the mobile phone BUT the 8 digit SIP Trunk account number is being displayed on the mobile phone display instead of the caller ID of the original number that made the call?

Any normal calls on the system will forward the Caller ID as normal and this only appears to be happening on any calls that go through VMX locator.

Can anyone please advise how to resolve this issue?