Trying to save muti track midi songs to PSR SX900 after changing instruments

[GLP]

Hello! New and technically illiterate evidently. I take a midi song that I find on this site load it on my PSR SX900, change the instruments on a couple of tracks and change the volume, pull up record, my song is there showing the changes I made, I press copy, I press execute, I press save here, I see a copy and I rename and It shows up on my USB with changes. I pull up a new song and go back to the song I made changes to and the changes are gone. What am I doing wrong?
I just want to copy a 16 track midi song, make minor changes like the instrument on the track and its volume. Save as a new song to my USB with the changes. Its got to be an easy thing but I guess not for me.
Thank you
GLP

[EileenL]

You have to go into the style creator to do this. Press Step record and select the track you want to alter.  Do your alterations if you want to alter more tracks do the same and then re-save the song.

[GLP]

Eileen,
Thank you I will give it a try.

[KurtAgain]

I think Eileen meant Song Creator and not Style Creator.

In the Lessons section there are lessons about adjusting songs: https://psrtutorial.com/lessons/tune/adjSong/index.html

Kurt