Hi @Anand ,
Thank you for posting query in Microsoft Q&A Platform.
From error message, it looks type cast issue. Integer value is not able to cast to string.
Could you please make sure your data types for columns in both source transformations matches with each other? under projection tab you can modify data types of your columns.
You can also use derived column transformation and use toString() function to type case specific column to string type.
Hope this helps. If not, could you please share your implementation of every transformation along with data preview at that transformation level. So that we can repro scenario and try to spot issue exactly.
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