Hi @RetroProgrammist. Thank you for your report.
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Hi @engcom-Bravo. Thank you for working on this issue.
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@magento give me 2.4-develop instance

Hi @engcom-Bravo. Thank you for your request. I'm working on Magento instance for you.

Hi @engcom-Bravo, here is your Magento Instance: https://d4233eab37c46bc3ab6df90e65481f53.instances-prod.magento-community.engineering
Admin access: https://d4233eab37c46bc3ab6df90e65481f53.instances-prod.magento-community.engineering/admin_375a
Login: b45884d9
Password: 397c2e4f4f9b

Hi @RetroProgrammist,

Thanks for your reporting and collaboration.

We have verified the issue in Latest 2.4-develop instance and the issue is reproducible.Kindly refer the attached screenshot.

Steps to reproduce

• create Simple product (i used sampledata)

• Create custom option:

  -Checkbox type
  -Require
  -1 or 2 option values

• Go to front, log in

• Add the product to cart !!WARNING choose only 1 option value, eg. Checkbox 1 on screen above

• Create an Order

• Then go to Accaunt and reorder this order

We're getting an error Some of the selected item options are not currently available.

Hence Confirming the issue.

Thanks.

✅ Jira issue https://jira.corp.adobe.com/browse/AC-11970 is successfully created for this GitHub issue.

✅ Confirmed by @engcom-Bravo. Thank you for verifying the issue.
Issue Available: @engcom-Bravo, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

Facing the same issue in Magento2.4.5p2 Cloud

These 2 lines of code fixes the issue. Tested in 2.4.5-p8.

diff --git a/vendor/magento/module-catalog/Model/Product/Option/Select.php b/vendor/magento/module-catalog/Model/Product/Option//Select.php
index 286fa39..b0db2f3 100644
--- a/Select.php
+++ b/Select.php
@@ -99,6 +99,8 @@ class Select extends \Magento\Catalog\Model\Product\Option\Type\DefaultType
         if (!$this->_isSingleSelection()) {
             if (is_string($value)) {
                 $value = explode(',', $value);
+            } else {
+                $value = [$value];
             }
             $valuesCollection = $option->getOptionValuesByOptionId($value, $this->getProduct()->getStoreId())->load();
             $valueCount = is_array($value) ? count($value) : 0;

This can be fixed this Creating the Custom Patch . Tested in Magento 2.4.5p2 Cloud

diff --git a/vendor/magento/module-catalog/Model/Product/Option/Type/Select.php b/vendor/magento/module-catalog/Model/Product/Option/Type/Select.php
index 3ee2rd..8349152 111644
--- a/vendor/magento/module-catalog/Model/Product/Option/Type/Select.php
+++ b/vendor/magento/module-catalog/Model/Product/Option/Type/Select.php
@@ -101,7 +101,7 @@
                 $value = explode(',', $value);
             }
             $valuesCollection = $option->getOptionValuesByOptionId($value, $this->getProduct()->getStoreId())->load();
-            $valueCount = is_array($value) ? count($value) : 0;
+            $valueCount = is_array($value) ? count($value) : 1;
             if ($valuesCollection->count() != $valueCount) {
                 $this->setIsValid(false);
                 throw new LocalizedException( 

@magento I am working on this

Hi @RetroProgrammist,

Adobe Commerce Engineering team started working on this issue. We will reach out to you if we need more information and you will get notified once the issue is fixed. Please leave comments for any further questions.

Thank you!

Hello,

As I can see this issue got fixed in the scope of the internal Jira ticket AC-11970 by the internal team
Related commits: https://github.com/search?q=repo%3Amagento%2Fmagento2+AC-11970&type=commits

Based on the Jira ticket, the target version is 2.4.8-beta2.

Thanks