Networking diagram:

Configuration Steps:

Step1. Access the gateway's management webpage, go to Network > MWAN, and Click on the ADD button.

Step2. Set the Interface Type to MAC based WAN Port. then click the Main Interface to WAN and enter Port Index.Enter the Username and Password given by your ISP. as shown in the following figure:

Repeat steps 1-2 above to add the remaining ADSL accounts.

Finally, you can see the ADSL line that has been given the IP address.