Error after editing a fill up

[RCSP]

I added a Fill up. Clicked Save. Went to the list of fuel ups, selected the fuel up I just added and clicked the edit symbol. Added a note "Pulled a trailer". Clicked SAVE. Error message appeared, made me select the % of city driving. I didn't change a thing, I just clicked SAVE. Would not let me proceed until I changed the % of city driving. I could change it then set it back to 50% and then I could click SAVE successfully.

This is repeatable 100% of the time.

Thanks!