Message type: E = Error
Message class:  FKK_ID_SEPA - FICA loc. cross-country SEPA messages 
Message number: 026
Message text: Bank not found in table BNKA(bank master data) for key & and BIC &.
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The SAP error message FKK_ID_SEPA026 indicates that the system could not find the specified bank in the bank master data table (BNKA) for the given bank key and BIC (Bank Identifier Code). This error typically occurs when you are trying to process a payment or create a SEPA file, and the bank information is either missing or incorrect.
Cause: Missing Bank Master Data: The bank key or BIC you are using does not exist in the BNKA table. This could be due to the bank not being set up in the system. Incorrect Bank Key or BIC: The bank key or BIC provided in the transaction does not match any entry in the BNKA table. Data Inconsistency: There may be inconsistencies in the bank master data, such as incorrect entries or missing information. Bank Deactivation: The bank might have been deactivated or marked as inactive in the system.
Solution: Check Bank Master Data: Go to transaction code FI01
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