You may have noticed that your Web SDK Auth Key has changed.
There are two possible explanations for that:
The "URL" field under "Settings > General" has changed
As the Auth Key is uniquely generated for your website, changing the URL will result in the generation of a new Auth Key. You should use this new one if you're seeing problems such as 401/403 errors towards batch.com in your browser's inspector.
Introduction of second generation Auth Keys
On 2019/07/09, we introduced a new format for the Auth Key. As a result, we regenerated all of the Auth Keys of the platform.
Old keys will continue to work indefinitely: there is no need to update your configuration with the new key.
You can check what kind of key you have by looking at its first characters: first generations keys start with "1." whereas second generation ones start with "2."