Message type: E = Error
Message class:  FOT_BTT - BTT Messages 
Message number: 003
Message text: BTT Code is not defined for the current transaction
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).
Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.
You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.
The SAP error message FOT_BTT003 indicates that a Business Transaction Type (BTT) code is not defined for the current transaction. This error typically arises in the context of SAP's Business Transaction Management (BTM) or when dealing with financial transactions that require specific BTT codes for processing.
Cause: Missing BTT Configuration: The BTT code required for the transaction has not been defined in the system. Incorrect Transaction Type: The transaction being processed may not be compatible with the BTT codes that are configured. Custom Development: If there are custom developments or enhancements, they may not have the necessary BTT codes defined. Transport Issues: If the configuration was recently transported from another system, the BTT codes may not have been included or activated.
Solution: Define the BTT Code: Go to the transaction code SPRO (SAP Reference IMG). Navigate to Financial Accounting (New) > Accounts Receivable and Accounts Payable > Business Transaction Types. Check if the required BTT code is defined. If not,
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
FOT_BTT002 Assignment for BTT Code &1 is missing
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FOT_BTT001 BTT Code &1 is undefined
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FOT_COMMON000 &1 &2 &3 &4
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FOT_COMMON001 CoCd. &1/GL Acct &2 is not linked to Tax Code &3
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
Click on this link to search all SAP messages.