Quickbook Desktop Pro in a single user license.

Thank you for posting your concern in the Community, @ptla.

Let me share information and guidelines to resolve your concern about using two devices for a single-user license QuickBooks Desktop (QBDT).

The user mode also matters when accessing your company file on multiple devices. This is why the transaction you entered using your desktop did not appear on your laptop. Single-user mode limits access to your company file to one person at a time.

With this, you'll want to switch to multi-user mode since QuickBooks Desktop uses a database file manager to communicate with the company file.

To turn on Hosting:

Important: Turn on hosting only for the Host computer or where the company file is stored. If you're using a server to host your file, one computer still has to act as a Host. You must not turn on hosting for workstations:

1. From the File menu, select Utilities.
2. Click Host Multi-User Access.
3. Click Yes on the confirmation window.
   
   

After turning this on, you'll want to follow these steps:

1. Go to your server computer (a computer that physically stores your company file).
2. At your server computer (hosting your company file/s), open the start menu and type the database.
3. ​Click on QuickBooks Database Server Manager.
4. If no folder locations are shown, click Browse and browse to the folder where you store your company file(s).
5. Click OK.
6. Click Start Scan, which will repair the firewall permissions to allow QuickBooks to communicate over your network and resolve your error.
7. When finished, click Close and try opening QuickBooks in Multi-User mode on your workstation(s).

I also added this article for more details about multi-user mode: Hosting your company data in multi-user mode in QuickBooks Desktop.

Otherwise, you'll have to manually back up the file from your desktop and restore it to your desktop. Though, every time you switch to a different station, you have to create a backup so you can view and use the current file. You can check out this article on how: Back up your QuickBooks Desktop company file.

To restore your backup file to the second computer. You can refer to this article for steps: Restore a backup of your company file.

You can read this article for reference: Move your company files to another computer.  

Please get back to me if you have further questions about moving data to another computer. I'm here to lend a hand. Have a great day!