Persisting old name of Mac during file transfer

I'm using macOS Ventura 13.4.1. Before migrating to my current Mac desktop, I changed the name of its predecessor from "MyMac" to "MyMacOLD" and then did the migration from TimeMachine. The new Mac is named "MyMac". Yet when I use file sharing from this new "MyMac" to a MacBook and transfer files from "MyMac" to the MacBook using a file comparison/transfer app (namely, VisualDiffer), each time I try a comparison of corresponding folders on the two machines, I get a pop-up error "There was a problem connecting to the server "MyMacOLD". If I just dismiss that pop-up, it pops up again; dismissing it again now allows the comparison of folders, and subsequent syncing via the app, to proceed. The Mac's SystemSettings > General > About shows the name as "MyMac" The situation persists even after I used all the steps shown at https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Setting-the-Mac-hostname-or-computer-name-from-the-terminal.html that use the terminal command scutil to set the name to "MyMac" (without the quotes, of course), including the restart. **Question:** Where is that name "MyMacOLD" being picked up from, and how can I fix it to be what my Mac is supposed to be named, "MyMac"?