Make sure your Line Account that you want to integrated is a Business Account.
These are the steps to add a LINE channel. First, go to “Setting” menu, choose “Account Channel” and then click “+Add Account”.
1. Click “[email protected]” Channel.
2. Fill the Credential information in the form below from your Line Businees Account. Once you have completed, click “Save” to proceed.
How to get a Line Business Credential to fill the form?
These are the steps to get a Line Business Credential
1. If the Line Account is not yet a Line Business Account , then you must setup it first, and follow the steps below :
– Go To https://account.line.biz/login
– Click “Create An Account” Fill in the registration form until the process is complete.
2. If you already have a Line Business Account,
– Login Your Account, Go To https://account.line.biz/login and then login with your Line Business Account.
– Click “Your Account Name”
– Click “Mode Respons” 
– Click “Messaging API” and then Click “Gunakan Messaging API” After that a window will appear for registering to the Developer Group Line. Then fill in according to the required data until the process is complete.
– Open new tab on your browser and Go To https://developer.line.biz , then in the products section select “Messaging API”
– Then click “Start now”
– After clicking “Start now”, the next page will display the settings containing the provider that was previously registered, then click “Your Provider Name” then click “Messaging API”
– Enable “Use Webhook” to actived and then input https://hook.sociomile.com/line/message?uid=<Channel ID> into webhook url click Update/Verify
– Click “issue” to get Channel Access Token
– Return to the official account Manager Line Panel input the Webhook url and then click save.
– Return to the sociommile settings page to make line integration to Sociomile, Fill the Credential information in the form below from your Line Businees Account. Once you have completed, click “Save” to proceed.
3. Your Line Business Account successfully connected to Sociomile