Update position number of bank statement transaction code to import custom bank code in MT940 file

In EBS, we are able to update the position of bank statement transaction code to a different value (from position 8 to position 8) so that a custom code can be imported. We want to implement the same in Oracle cloud, but the Manage Bank Statement mapping setup is missing. How can we update the mapping of code in MT940 format file? Example, transaction code should be number 2504 in the end-

:61:2502190219CM281062714,00NTRFPAGO UNID PLAN M//2504