Message type: E = Error
Message class:  FIORI_MYCONTACTS_MSG - Message class for My Contact Fiori App 
Message number: 004
Message text: Internal error: BAdI error &1 &2 &3 &4
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The SAP error message FIORI_MYCONTACTS_MSG004 with the description "Internal error: BAdI error &1 &2 &3 &4" typically indicates an issue related to a Business Add-In (BAdI) implementation in the SAP Fiori application, specifically in the context of the "My Contacts" app.
Cause: BAdI Implementation Issues: The error often arises from a problem in the BAdI implementation that is being called by the Fiori app. This could be due to: Missing or incorrect implementation of the BAdI. Errors in the code of the BAdI implementation. Incompatibility between the BAdI and the Fiori app version. Data Issues: Sometimes, the data being processed by the BAdI may not meet the expected format or constraints, leading to runtime errors. Authorization Issues: Lack of proper authorizations for the user executing the Fiori app can also lead to internal errors.
Solution: Check BAdI Implementation: Go to transaction SE18 (BAdI Definition) and SE19 (BAdI Implementation) to check if the BAdI related to the "My Contacts" app is
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