User Auto login and open user channel page without ask for login

Hi There,

I have developed mattermost login API code in PHP to auto login for user. The php login script request the login API and create cookie of token which I get in API response header.
Now I want to redirect the user to their channel after getting the token in login API response.
But I stuck here, when I redirect the users to their channel URL the mattemost ask for login authentication.

I have search around the net but didn’t getting any way to do this,
Please help me to fix it.