Budget control Incorrect source

Summary:

Hello, I have created a DFF as 'Budget Reference Number' under Attribute2

Now when i create the Mapping set, I am a bit confused which Input source to choose since I am having an error message at TAD level.

Please help which 'Source' to choose?

The error can be reproduced by following the steps below:

1. Add DFF Budget Reference Number
2. Create a mapping set

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