Message type: E = Error
Message class:  FI - TR-FM Funds Management 
Message number: 018
Message text: Enter only one FM area
You are trying to select several FM areas for the drilldown report to
be carried out. You also want to display budget structure elements. If
you want to carry out a drilldown report with budget structure
elements, then this is only ever possible for one FM area since the
budget structure is FM area-dependent.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Change your selection criteria so that only one FM area is selected.
You must make this change either on the selection screen, or in the
drilldown report or in the form.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FI018 ("Enter only one FM area") typically occurs in the context of Financial Accounting (FI) and Funds Management (FM) when a user attempts to enter or process data that involves multiple Funds Management areas in a single transaction or entry. This error is designed to ensure that only one FM area is processed at a time, as mixing multiple FM areas can lead to inconsistencies and errors in financial reporting and management.
Cause:
Multiple FM Areas Selected: The user may have inadvertently selected or entered multiple FM areas in a transaction that only allows for one.
Configuration Issues: There may be a configuration issue in the system that allows for multiple FM areas to be selected when it should not be.
Data Entry Error: The user may have made a mistake while entering data, such as copying and pasting information that includes multiple FM areas.
Solution:
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