3821514 - How do I claim M&IE expenses after an travel allowance itinerary is already submitted?

One of users had submitted an expense report and was paid for the expense and their M&IE for recent trip was not included. However, when I try and add the travel itinerary, it states that adding this row would cause an overlap. How can I pay use for the the missed M&IE for this trip?

How do I claim M&IE expenses after an travel allowance itinerary is already submitted? , KBA , CON-EXP-ADM-TA , Travel Allowance , Problem