Structures are not allowed to be initialized without initializing all of its members. You have to add a constructor like this.
USTRUCT(BlueprintType)
struct FSAnswerText
{
GENERATED_BODY()
public :
UPROPERTY(BlueprintReadWrite, EditAnywhere)
FText FTAnswerText;
UPROPERTY(BlueprintReadWrite, EditAnywhere)
float DelayTime;
FSAnswerText() : FTAnswerText (DEFAULT_VALUE), DelayTime(DEFAULT_VALUE)
{
}
};
Remember to add the DEFAULT_VALUES, it´s just a placeholder for the answer.
Hope it helps.