205tcc no aperture information in display

hello,
i have 205tcc for about 10 years in very good condition.
i shoot with the camera very rarely and in the beginning everything worked just fine.
at some point, about 3 years ago the display stopped showing the aperture number, instead two dashes (- -).
i have two original 205tcc lenses (80mm and 50mm), i get the same behaviour with bot lenses. the lenses are also in mint condition.
the camera was already twice in independent repair shops but was returned back with the advice to send it to the factory in sweden.
no one was sure what exactly the problem. some say it is the controller of the metering or the flex cable between the lens contact and the controller.
im not sure if both technicians were very good hasselblad specialists.
 
all other functions of the metering and all different programs are shown correctly in the display.
 

 

i would be grateful for any advices.

 

thanks!