You can send support emails to firstname.lastname@example.org
if you prefer that method to the forums. This information can be found on the 'Contact Us' page.
If the additional episodes still show as Coming Soon, you will need to shut down the game application and restart your device. Make sure you are logged into the account you used to purchase the Walking Dead, and then re-launch the game. When you do this, you will see a black screen for a few moments. This is normal as an update will need to download. Afterward you should be able to download other episodes from the in-game episodes menu.