@T5-T6-Schnappi thanks. actually, i have an idea it could be from battery, as it is old. Voltage was over 12 volt, but maybe dropped during the process?
i didnt see any requirement to use charger during process?

@T5-T6-Schnappi thank you, unfortunately didnt know that.
anyway, after battery change, all errors (apart of that airbag service required) vanished,

@T5-T6-Schnappi thanks for your assisstance. Indeed, you were right with car incompatibility with new settings. I got new charger today and reverted belt reminder to original (Euro NCAP), and message was immediately gone.
Thanks!