expense report created for non-authorized expenses

Hello,

We are using 12.1.3 and have the following issue:

An user created an expense report for a personal expense which is against our Corporate policies and an invoice were created then they add a positive line to the invoice to have a final value of zero.

We have an invoice of zero value and not paid and they cannot reconcile it.

I think they should use the same account of the first line and they should pay the invoice even if is zero.

In Summary:

Line 1     (38.00)     account 20040

Line 2      38.00      account 20000

I think they should not manually add the second line but they should raise a Debit memo, is this correct?