diff --git a/.github/workflows/instance-destroy-test.yml b/.github/workflows/instance-destroy-test.yml
index d1539f8..178fd80 100644
--- a/.github/workflows/instance-destroy-test.yml
+++ b/.github/workflows/instance-destroy-test.yml
@@ -36,6 +36,6 @@ jobs:
         env:
           TF_VAR_acr_username: "not-used"
           TF_VAR_acr_password: "not-used"
-          TF_VAR_website_dns_subdomain: "not-used"
-          TF_VAR_api_dns_subdomain: "not-used"
-          TF_VAR_monitoring_dns_subdomain: "not-used"
+          TF_VAR_website_dns_subdomain: ${{ github.head_ref }}-website
+          TF_VAR_api_dns_subdomain: ${{ github.head_ref }}-api
+          TF_VAR_monitoring_dns_subdomain: ${{ github.head_ref }}-monitoring
diff --git a/terraform/instance/container_apps_bind_dns/scripts/destroy.sh b/terraform/instance/container_apps_bind_dns/scripts/destroy.sh
index 1c3d6ac..44febdf 100644
--- a/terraform/instance/container_apps_bind_dns/scripts/destroy.sh
+++ b/terraform/instance/container_apps_bind_dns/scripts/destroy.sh
@@ -7,6 +7,30 @@ die() {
   exit 111
 }
 
+# remove the custom domain from the container app
+az containerapp hostname delete --hostname $CUSTOM_DOMAIN \
+  -g $CONTAINER_APP_RESOURCE_GROUP \
+  -n $CONTAINER_APP_NAME
+echo "removed the custom domain from the container app"
+
+# wait for the custom domain to be removed
+tries=0
+until [ "$tries" -ge 12 ]; do
+  [[ -z $(
+    az containerapp hostname list \
+      -n $CONTAINER_APP_NAME \
+      -g $CONTAINER_APP_RESOURCE_GROUP \
+      --query "[?name=='$CUSTOM_DOMAIN'].name" \
+      --output tsv
+  ) ]] && break
+  tries=$((tries + 1))
+
+  sleep 10
+done
+if [ "$tries" -ge 12 ]; then
+  die "waited for 2 minutes, checked the containerapp 12 times and it still has the custom domain. check azure portal..."
+fi
+
 # get the managed cert using the custom domain
 CERTIFICATE_ID=$(
   az containerapp env certificate list \