Please check your subscription preferences. First, log in to Alpha Builder, and then click on the "Profile" icon in the top right corner (looks like a person). Then click on "Edit Profile" and scroll down to "Email Notifications."
You should see the 3 options below. If you select the third choice, you can choose which notifications you will receive.
Make sure you have checkmarked the first square box in order to receive weekly session emails related to your current Alpha. If you still don't receive the updates, please let us know and we can look into this for you.