Charges not "registering" on new credit card account

[Jan Dubois]

I created a new credit card account in GnuCash 2.6.5 today (for a
Canadian Capital One Costco Mastercard). I've downloaded transactions
in *.qfx format from their website and imported them into GnuCash.

All transactions show up in the register page for the new account, but
the "Charge" field is always empty (and the "Balance" remains
unchanged).

When I select a record in the register and "Jump" to the corresponding
record in the expense account, the record shows up and does include
the correct value in the "Expense" column?

I have other (older) credit card accounts (but not for Capital One),
that import transactions correctly.

How/why does this happen, and what can I do to fix this?

Cheers,
-Jan