Note: with Conditional Fields Pro it’s now possible to use the same field name multiple times with the disable_on_hide attribute

Even though your fields might never show up at the same time, it is still important to realize that WPCF7CF will not remove the fields, it merely hides them. So all fields will be submitted when the form is sent. Because of this no two fields can have the same name. This also includes group names.

Incorrect form (2 input elements having the same name “a”):

[group group-1][select a "1" "2" "3"][/group]
[group group-2][select a "1" "2" "3"][/group]

Correct form (all groups and fields have unique names):

[group group-1][select a "1" "2" "3"][/group]
[group group-2][select b "1" "2" "3"][/group]