Music files do also contain metadata ‘tags’ that can be read with tag editors, players, apps, viewers etc. so maybe the ‘view’ you're seeing in the chosen app is ordering the tracks by those tags. I would check the App you’re using and see if there’s a way to change the sort-order to their file name.

Gawd. Thanks but not IT capable enough for this! Need to find a face to face local expert.

Does the App you’re using allow you to create a playlist,  or does it show you the queued music? - I’m thinking perhaps just create a playlist in the track-order you want it to play, or maybe edit the playing queue in its ‘now playing’ screen, if either of those things are available and perhaps any easier for you to do instead?

Can't find any facility to do queue or play list.

The app I've got is 'Files'. Maybe I need a different app..??

Google Files that is.

I use Apple iOS device mostly myself, but maybe others here in the community will chime in and suggest other Apps. I assume though that when you select to play the tracks from your files that they load into a music player, so it’s in that App you need to sort the track order, perhaps ?

Thank you. My phone is Android.  Have tried sorting in 2 different apps now...no go. Thanks anyway.