false validation error

Simple form:

[radio radio-1 use_label_element "1" "2" "3"]

[group group-1 inline] [radio radio-2 use_label_element "1 a" "1 b" "1 c"] [/group]

[group group-2 inline] [radio radio-3 use_label_element "2 a" "2 b" "2c"] [/group]

[group group-3 inline] [radio radio-4 use_label_element "3 a" "3 b" "3 c"] [/group]

with conditional logic

show [group-1] if [radio-1] equals "1"
show [group-2] if [radio-1] equals "2"
show [group-3] if [radio-1] equals "3"

Select something in group 2, than switch to group 1 – validation error
Select something in group 3, than switch to group 1, or 2 – validation error

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