Can not invoke autotune anymore (after rebuild)

Hi guys,
after my crash I built a complete new quad on Tarot 650 Sport base. I have not changed my RC and the general settings, but now I have the following problem:
I use a 2 Pos and a 3 Pos switch to change the flight modes. This works fine. With another switch I do an override of channel 7 with PWM > 1800. That worked fine on my old copter with same hardware. Now I get always “Flight mode change failed” when I try to engage autotune. I could always check in MP that autotune is invoked, now it does not work at all. With e.g. “Brake” it works perfect, but not with autotune.
Has any of you experienced guys an idea? This would really help me.
Best regards,
Chris

Problem solved…

I put Rover Firmware to my FC and afterwards Copter again, did setup from ground and now it is working fine…

Greetings from sunny south-west Germany,

Chris