my midi keyboard roland A500 pro does not work anymore in logic pro X

I'm using a midi keyboard controller Roland A500 pro but it doesn't work anymore while using logic pro X. Although, in preferences it is assigned as my controller. I've changed cables and usb portals. I've unplugged the controller, restart the iMac and plugged it back in again. I've checked if the device if is compatible with Sierra, no problem there. The controller works because i've used it last week during a performance. Can anyone help me ?