I suspect you have a midi file, and while using this file on the PC - using software ?? - you disabled the guitar part. It may be possible to 'edit it out', but that's not easy. Anyway, the guitar part was prob still there, but disabled, so not heard.
Then maybe you moved the midi file to your keyboard? The file still contains the guitar part, but the disabling is in the software, not the midi data, so on the keyboard it's no longer disabled? When you play the file on the keyboard, the guitar part is back again (as it's no longer disabled).
So, you need to disable this instrument on the keyboard, which may have a way to do this, but the way could be quite different to how it was done in the software on the PC. OR, you need to find a way to edit/change the midi file to remove it totally (maybe by assigning the instrument to a channel that the keyboard does not play, or by altering the instrument to something that does not sound, or setting the volume to zero, etc).
With somewhat more detail, I might be able to suggest other things. OR, if I had the midi file, I could remove the guitar part totally.