The SoC detected with an OBDII dongle is different from the one shown in the car.
The difference is about 7%.
In particular, when the car shows 80%, ABRP displays 73% and when the car shows 70% ABRP displays 63%.
Have you made sure that live SoC is enabled in settings so that ABRP is not starting out from a manually entered value?
The button to the right of the SoC input in settings should be filled blue, alternatively you can just toggle on 'automatic settings' at the top of the settings menu to enable live SoC, reference consumption etc.