@Wesley Lacroix
This is likely a phishing attack to get your login credentials.
I am not aware of that email address or the existence of such a portal. Therefore, it sounds suspicious to me and automated Docusign emails use docusign.net as domain. The email sender may be have faked as well, depending on your email software this may be easily identified or not.
What is the URL that you are redirected to? It sounds like you clicked on the link and were presented with a login page.
You can access your invoice after you log into your Docusign account at https://app.docusign.com
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