Chord Tracker with tyros5

[Tezwalker]

 Hi chord tracker prob.   To learn a song I find a mp3 and download to chord tracker  where the chord are displayed so I load to tyros find a style and start the midi which plays  the chords to the style so l can play melody the chords are displayed on screen

Now cones the prob if I play on top part of keyboard on tyros no problem if I go in to lower part style
The mildi stops playing the chords

Now comes main prob I have a midi keyboard connected through midi A on tyros which is set to copy tyros but if I touch any key on lower keyboard  the chords stop playing  the display where the chords are displayed says cancel/A if I play a A key and so on  any ideas thank

Terry