Urgent: Developer Application & Application Fee Stuck on Abandoned Square Account and Blocking Active Development

I’m dealing with an urgent Square Developer account issue and need guidance on the correct next step.

The Square Developer application for my third-party restaurant ordering platform was created under an older Square account. That application is what handles the application fee/commission from restaurant orders.

The restaurant stopped using that Square account about two weeks ago because a former owner still had access to the account credentials, so a new Square merchant account was created for the restaurant.

The problem is that the existing Developer application and application-fee setup are still tied to the old account. My developer is actively working on the integration right now and needs access to the correct application/Sandbox environment, so this is currently blocking the project and costing me development time.

What I need to understand is the correct Square-supported process to get the Developer application/application-fee setup back under my third-party company’s control and then connect the restaurant’s new Square merchant account to that application.

If the existing application cannot be transferred or recovered, I also need to know the correct migration process so we can move forward without breaking the live ordering/payment integration.

I can provide the Application ID, merchant IDs, business verification, or any other information privately to Square staff.

Any help getting this escalated would be greatly appreciated because development is currently blocked.

Following up because this is now actively blocking production work on our restaurant ordering application.

Our developer is currently working on the integration, but the existing Square developer application/application-fee setup is tied to an older Square account that the business no longer uses or controls. We need guidance on the correct supported path to either regain/migrate control of the existing application or move the integration and application-fee setup to the current account we control.

This is a live production system and development is currently in progress, so any assistance from Square Developer Support would be greatly appreciated. I can provide the Application ID and other account details privately if needed.