Hi,
Have you checked the actual files from the File Explorer if they have the names you've entered? As far as I know, if you're changing the track names in Windows Media Player, those changes won't be reflected in the actual file names. Also, Windows Media Player no longer supports the Find album info feature, as Microsoft discontinued this service last year. This means your tracks will no longer have their metadata automatically populated through WMP.
To have your tracks properly renamed, right-click on it in Windows Media Player and select Open file location. This will open the folder where you'll see the files named Track 1, Track 2, and so on. Rename the files directly from that folder so they retain your preferred names when you transfer them to your mobile device.