Using Roland keyboard with Halion in Cubase 10.5

I am using an old Roland RD700 stage piano as my midi controller.
When I select an instrument in Halion and activate it with the keyboard I hear both the keyboard sound and the Halion sound.
(I can use the keyboard sounds to record/playback ok on their own outside Halion).
Any comments much appreciated.

Hi and welcome to the forum,

Set Local Control Off on the RD700 to disconnect its keyboard from the synth engine.

Thank you so much.