Message type: E = Error
Message class:  FI - TR-FM Funds Management 
Message number: 306
Message text: No commitment item assigned to G/L account &/&, or assignment not valid
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Assign a postable commitment item to the G/L account.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FI306 ("No commitment item assigned to G/L account &/&, or assignment not valid") typically occurs in the context of financial accounting and controlling when there is an attempt to post a transaction that requires a commitment item, but the specified General Ledger (G/L) account does not have a commitment item assigned to it.
Cause:
Missing Commitment Item: The G/L account you are trying to use does not have a commitment item assigned in the system.
Invalid Assignment: The combination of the G/L account and the commitment item is not valid or does not exist in the configuration.
Configuration Issues: The settings in the controlling area or the G/L account may not be properly configured to allow for the assignment of commitment items.
Solution:
Check G/L Account Configuration:
Go to the transaction code FS00 (G/L Account Master Record) and check the configuration of the G/L account in question.
Ensure that the commitment item is assigned Get instant SAP help. Sign up for our Free Essentials Plan.
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