User is able to update Accounted Amount in Journal line for Foreign Currency Journal for Spot Rate

Summary: User is able to update Accounted Amount in Journal line for Foreign Currency Journal for Spot Rate

Content (please ensure you mask any confidential information): When users are entering foreign currency journals and using rate type as Spot (or not equal to User) , the system is calculating Accounted Amount as per Spot rate in the journal lines but the Accounted Amount field is editable and user can overwrite the Accounted amount calculated by the system. Users does not want system to work in this manner and they wanted Accounted amount to be grayed out field in case Spot rate type is used and system is calculating the accounted amount so that users can not update it. Could you please let us know how that can be