Logic

a!localVariables(
  local!q1,
  local!q2,
  {
  a!columnsLayout(
    columns: {
      a!columnLayout(
        contents: {
          a!dropdownField(
            choiceLabels: {"Yes","No"},
            choiceValues: {"Yes","No"},
            label: "Question 1",
            labelPosition: "ABOVE",
            placeholder: "--- Select a Value ---",
            value: local!q1,
            saveInto: {
              local!q1,
              if(
                local!q1="Yes",
                a!save(
                  local!q2,
                  "No"
                ),
                {}
              )
            },
            searchDisplay: "AUTO",
            validations: {}
          )
        }
      ),
      a!columnLayout(
        contents: {
          a!dropdownField(
            choiceLabels: {"Yes","No"},
            choiceValues: {"Yes","No"},
            label: "Question 1",
            labelPosition: "ABOVE",
            placeholder: "--- Select a Value ---",
           value: local!q2,
            saveInto: {
              local!q2,
              if(
                local!q2="Yes",
                a!save(
                  local!q1,
                  "No"
                ),
                {}
              )
            },
            searchDisplay: "AUTO",
            validations: {}
          )
        }
      ),
      a!columnLayout(
        contents: {}
      )
    }
  )
}
)

try the above code and see if it works for you