I got a domain (skhole.club) from Route 53 and automatically generated a host zone skhole.club.
And I created a new host zone alb.skhole.club.
Records are added by my terraform codes.
When I run the dig command in skhole.club, dig returns records.
On the other hand, alb.skhole.club returns no records.

This is the first time using a custom domain so I may make an elementary mistake.
Any Solutions or Hints?

Terraform file (route53.tf)

version

required_providers {
  aws = {
    source  = "hashicorp/aws"
    version = "4.59.0"
  }
}

data "aws_route53_zone" "host_domain" {
  name = local.host_domain
}

data "aws_route53_zone" "alb" {
  name = "alb.${local.host_domain}"
}

resource "aws_route53_record" "cert_validation" {
  for_each = {
    for dvo in aws_acm_certificate.cert.domain_validation_options : dvo.domain_name => {
      name   = dvo.resource_record_name
      record = dvo.resource_record_value
      type   = dvo.resource_record_type
    }
  }

  allow_overwrite = true
  name            = each.value.name
  records         = [each.value.record]
  ttl             = 60
  type            = each.value.type
  zone_id         = data.aws_route53_zone.host_domain.zone_id
}

resource "aws_route53_record" "cert_alb" {
  for_each = {
    for dvo in aws_acm_certificate.cert.domain_validation_options : dvo.domain_name => {
      name   = dvo.resource_record_name
      record = dvo.resource_record_value
      type   = dvo.resource_record_type
    } if length(regexall("^\\*\\.", dvo.domain_name)) == 0
  }

  allow_overwrite = true
  name            = each.value.name
  records         = [each.value.record]
  ttl             = 60
  type            = each.value.type
  zone_id         = data.aws_route53_zone.alb.zone_id
}

resource "aws_acm_certificate" "cert" {
  domain_name               = local.host_domain
  subject_alternative_names = ["alb.${local.host_domain}"]
  validation_method         = "DNS"

  tags = {
    Environment = var.app_environment
  }

  lifecycle {
    create_before_destroy = true
  }
}

resource "aws_acm_certificate_validation" "cert" {
  certificate_arn         = aws_acm_certificate.cert.arn
  validation_record_fqdns = [for record in aws_route53_record.cert_validation : record.fqdn]
}

resource "aws_acm_certificate_validation" "alb" {
  certificate_arn         = aws_acm_certificate.cert.arn
  validation_record_fqdns = [for dvo in aws_acm_certificate.cert.domain_validation_options : dvo.resource_record_name]
}

resource "aws_route53_record" "site" {
  zone_id = data.aws_route53_zone.host_domain.zone_id
  name    = local.host_domain
  type    = "A"

  alias {
    name                   = aws_cloudfront_distribution.static-skhole.domain_name
    zone_id                = aws_cloudfront_distribution.static-skhole.hosted_zone_id
    evaluate_target_health = false
  }
}

resource "aws_route53_record" "alb" {
  zone_id = data.aws_route53_zone.alb.zone_id
  name    = "alb.${local.host_domain}"
  type    = "A"

  alias {
    name                   = aws_lb.application_load_balancer.dns_name
    zone_id                = aws_lb.application_load_balancer.zone_id
    evaluate_target_health = false
  }
}

Route 53 Console

skhole.club

alb.skhole.club

dig command response

dig skhole.club

> dig skhole.club ns +short
ns-306.awsdns-38.com.
ns-1898.awsdns-45.co.uk.
ns-1111.awsdns-10.org.
ns-526.awsdns-01.net.

dig alb.skhole.club (no response)

> dig alb.skhole.club ns +short

Solved

The subdomain should be in the main domain host zone.

>Solution :

Do not create a separate Hosted Zone for the subdomain.

Instead, simply create the Alias=Yes A-record in the original Hosted Zone with a record name of alb.skhole.club.