Open any browser like Chrome

type 192.168.1.254 on address and click go or enter

BT Hub admin page will show

Advanced Settings.

My Network

Find POS router and click.

Set to use alway this IP address

Click SAVE button on top right

Firewall.

Click on the Create a new port forwarding rule button on the right hand side.

You will then need to specify the following -
Rule name:  POS.

Select device: Find POS router and select.

External and internal ports: Start: 22 ,  End: 80 for both

Protocol: Select TCP/UDP.

Click + button

Click Save