Update Theme

Firstly, you need to download the new theme package from your Themeforest account. Once you have the new theme package, you can choose to upload the theme via WordPress or via FTP.

Update theme via WordPress

Step 1: You need to deactivate the current Transport theme in Appearance > Themes section by simply activating a different theme. Once you activate a different theme, you can go to Theme Details and delete the Transport.

Step 2: Retrieve the Transport.zip file from your new Themeforest download. If you download All files & documentation, then you need to unzip the archive file you received, the Transport.zip file will be inside of it.

Step 3: Then simply upload and activate the Transport file in the Appearance > Themes section like you've done when installing theme.