Multiple Mapping Error in DMM

Hi Experts,

I am creating DMM using the ETL Wizard. during my process, in the mapping editor i am mapping two source columns to one single target column. and when i validated the model i am facing error as Multiple mapping error.

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How can i resolve this error, i need to map the source two columns to one target column.

Error:

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Thanks in Advance

PrasannaKumar.