Fixed wing V-Tail ruddervators not going to default positions - Stabilized mode - QGC | CUBE Orange| Px4 stack

I have a configured my V-tail Fixed wing mini Talon on a CUBE Orange FC with Px4 stack using QGC platform.
While in manual mode everything works pretty well. But when I change to Stabilized mode, the Ailerons are positioned in-line with the control surfaces but the V-Tail ruddervators don’t go to default positions for a stabilized flight mode for a V-tail configuration. My Air frame is XUAV mini Talon .

Can you give some suggestions here . This may be a general troubleshoot procedure.