Use the below steps to configure L2TP on your Windows phone:
1. Go to Settings and then click on VPN.
2. Click on the Plus (+) sign to create a new VPN profile.
3. Enter the following details:
Server name: Enter the server address that you wish to connect to. You can get the list of servers from here
Type: Choose L2TP with IPSec from the drop-down menu;
Connect using: Tap on Choose an item. Then tap on user name + password + preshared key.
4. Scroll down and enter the following:
Username: LimeVPN username
Password: LimeVPN password
Preshared Key: private
NOTE: If you are using a dedicated IP (LimeVPN Pro), then the Pre-shared key will be limevpn
5. Turn on the following features:
Connect Automatically: On;
Send all traffic: On;
You can rename your VPN profile to a name of your choice.. When you are done, please double-check the settings you have changed and tap Save.
6. To make sure your connection is not dropped when your phone goes into sleep mode, tap and hold the VPN profile you created, and select Manual instead of Automatic.