Custom Validation Annotation not working properly using java 8 @Repeatable

ADDITIONAL SYSTEM INFORMATION :
Java version : 1.8.0_121

A DESCRIPTION OF THE PROBLEM :
Recently I added @Repeatable to my custom annotations. Once i added repeating annotaion to fields it was working fine , but fields with single annotoation is not working.

Example:

Following works:

@NotNull
@CustomValidator(type = Type.SIZE, max = 80)
@CustomValidator(type = Type.FIELD)
private String firstName;
But following does not works(Since it contains only one @CustomValidator):

@NotNull
@CustomValidator(type = Type.EMAIL)
private String email;
CustomValidator.java

@Constraint(validatedBy = CustomValidatorImpl.class)
@Repeatable(RepeatableCustomValidator.class)
public @interface CustomValidator {

    String message() default "";

    int min() default 1;

    int max() default Integer.MAX_VALUE;

    String format() default "dd.MM.yyyy";

    String[] values() default {};

    Type type();

    boolean optional() default false;

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};
}
RepeatableCustomValidator.java

@Target({ ElementType.FIELD })
@Retention(RetentionPolicy.RUNTIME)
public @interface RepeatableCustomValidator {
    CustomValidator[] value();
}


Stack Overflow link : https://stackoverflow.com/questions/52382755/custom-validation-annotations-not-working-properly-using-java-8-repeatable

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Field with single custom validation annotations must also work.

CUSTOMER SUBMITTED WORKAROUND :
Added extra Custom annotation at class level .

FREQUENCY : always