MMDVM_HS_Dual_hat Problem

[on6dp]

HI,
I have a PiStar 4.1.0 RC7 and the boot is on SSD HD via USB3.0
All is OK, the soft is running but the MMDVM Modem is not detected by Pi-Star and is well connected to the GPIO 40 pins
It seems that it's a problem on soft because the modem is running well on another Pi board

Strange, when I'm launching the pistar-findmodem, the modem is well detected like this :

Detected MMDVM_HS (GPIO): /dev/ttyAMA0 (MMDVM_HS_Dual_Hat-v1.4.17 20190529 14.7456MHz dual ADF7021 FW by CA6JAU GitID #cc451c4)

When I 'm trying to upgrade the firmware I have the following error message I have is :

Got byte 0x0b instead of ACK
Unexpected reply from device on command 0x00

Anybody has a solution to me ?
73 Paul