Would you be able to share more context with us on how and where you're being asked for this info so we can look into this with you?
Is this something you need to add within your Shopify admin, or are you being asked for this by a third-party platform or service?
Let us know if this is information being requested by a payment gateway provider, so that we can share steps on how you can access the relevant ID info for your store.
If this is external to Shopify, please share any links or documentation you're referring to that might help us to understand what this is and where it can be located.
The more information you can give us here the better we will be able to understand and help out.
I look forward to investigating this with you!
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