Need to add credit memos in a PPR through some form of integration, such as API, WebService or FBDI

Summary:

We need to add credit memos in a PPR through some form of integration, such as API, WebService, FBDI, etc. How can we accomplish this, please?

While I comprehend the process of inserting a credit memo in a PPR through the UI, we are currently facing challenges when attempting to achieve the same through integration processes. 

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23C

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