@Butters @Boki
Thank you very much to both of you for time and effort to help and clarify this to me.
Regarding this last option proposed by @Butters I will certainly try in next few days to connect device to a Linux computer to see is it possible to access the device. I will inform back.
Best regards.
UPDATE: The owner (my good friend) figured out that he still have warranty for this device from the Official Garmin Store (1 more month of warranty period). They said that they will try to solve the problem we will see.
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