Hello,
I imported an Excel file with credit card transactions via DMF, and for 2 employees I received this error.
Therefore, I went to Human resources > Workers > Employees, I selected the employee and I clicked to Expense > Edit > Credit card. The settings seems to be the same of the others employees, with only the last 4 numbers of the credit card inserted (this seems to me strange, are the last 4 number sufficient to identify a credit card?).
Is there any other place in the system that I have to check to solve this problem?