Data custom field is not reported into basket

Suppose I have only two products: A and B.
Product A has got a custom field, text type.
When someone buys product A, custom field value goes correctly into basket

Product B has got a custom field, data type.
When someone buys product B, custom field value is NOT mentioned into basket. So, this value is lost.

Can you help me on that? Thanks

Hi,
Firstly, can you show me some screenshots of your issue and of how did you configured your custom fields, so that I can understand your issue ?
Thanks .