This is May from Shopify.
Just to clarify, are you referring to your printed POS receipt? Generally, POS receipts should have sales tax/VAT, and the grand total of the order. Here is an example of what a printed POS receipt should look like:
If your receipt does not look like the image above, it could be because VAT has its own area inside the tax section of the admin, hence it generates differently. It is quite difficult to troubleshoot the issue without looking directly into your account. That said, I am going to send you an email to the email address attached to your forum account, so we can take a further look into it.
Keep your eyes peeled for the email!