Message type: E = Error
Message class:  FKKINV - Invoicing in Contract Accounts Receivable and Payable 
Message number: 021
Message text: Number range &1 (Object &3) is incorrect for document type &2
Number range &V1& was deleted in number range object &V4& or was created
incorrectly.
The document was not posted.
Assign a number range from which numbers can be assigned to document
type &V2&.
Correct number range &V1& or recreate it if it was deleted in error.
Delete any "full" number ranges.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message FKKINV021 indicates that there is an issue with the number range configuration for a specific document type in the context of the SAP Contract Accounts Receivable and Payable (FI-CA) module. This error typically arises when the system attempts to generate a document number for an invoice or other financial document, but the number range assigned to that document type is either not defined, not active, or has been exhausted.
Cause: Incorrect Number Range Configuration: The number range for the specified document type is not set up correctly in the system. Inactive Number Range: The number range might be inactive or not assigned to the relevant document type. Exhausted Number Range: The number range has been exhausted, meaning that all available numbers have been used up. Missing Authorization: The user may not have the necessary authorizations to access or use the number range.
Solution: To resolve the error, follow these steps: Check Number Range Configuration: Go
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