Blocked from publishing new apps — existing verified account inaccessible.

In 2018, a KnowledgeOwl Azure AD (Entra ID) application gallery listing was published. The listing is still live in the Marketplace under Entra ID apps, but our company cannot manage it.

When we log into Partner Center with the email that received the 2018 notifications, we have no way to view the listing or submit support requests. Under Account settings > Legal info > Developer, we can see what appears to be our publisher info, including our Seller ID and Windows Publisher ID.

How can we regain access to manage this listing, or submit a support request? We are wanting to publish new apps (Teams, Copilot, Graph Connector) and are currently blocked. Customers are waiting on this.