This is not an iD Mobile related issue. 

Hi ​@mburns453 

Thank you for getting in touch with us, please confirm if you experiencing the same issue if you use iD Mobile SIM?

Thank you,

Zandile 

Hi there,

this issue is only with the ID sim, I was previously with Vodafone and wifi calling worked on that WiFi and now with ID it does not

Vodafone’s implementation of Wi-Fi calling won't be the same as THREE’s as there is no set standard in use across all networks. They can all use different ports and protocols. 

Three UK Wi-Fi calling typically requires specific firewall ports to be open for IPSec VPN connectivity, which is used to tunnel voice traffic. The essential ports are UDP 500 (IKE), UDP 4500 (NAT-Traversal), and often IP Protocol 50 (ESP). Ensuring these, along with proper SIP signaling (UDP/TCP 5060), are open on restricted networks enables the service. 

• UDP 500: Used for IKE (Internet Key Exchange) to establish the secure VPN tunnel.
• UDP 4500: Used for NAT-Traversal (NAT-T) to allow IPSec traffic through home/public routers.
• IP Protocol 50 (ESP): Encapsulating Security Payload, crucial for encrypting the data. 

If calls still fail, check for firewall restrictions on UDP traffic and ensure your router allows IPSec pass-through. 

Hi ​@mburns453 

Thank you for your message, and I’m sorry for the inconvenience you’re experiencing with Wi-Fi calling.

I understand that this issue only occurs with your ID SIM, and that Wi-Fi calling worked previously with Vodafone on the same Wi-Fi network. We’ll need to check your account settings and the provisioning for Wi-Fi calling to ensure everything is correctly enabled on your ID SIM.

Please send us a private message so we can securely access your account and investigate this further.

Thank you,

Zandile 

Hi Zandile, 

Could you please reach out over private message as it will not let me send one!