Custom field is not displayed in order

Hi there,
I created one custom checkout field (for VAT number) and it is correctly displayed on the checkout page. When an order is processed that custom field is not displayed in the page of the single order though. In the single order page all the default information is there but not this checkout custom field. That field is also not displayed in the e-mails but this is less important.

It is not clear to me whether this is a Pro feature or there is a plug-in conflict.

I read your answers to similar questions but there are no custom fields displayed in the bottom of the order page (in admin). I think because I use the Advanced Custom Fields plug-in but I am not sure this is the problem.

Is this the intended behavior?

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