When creating a payment in Quickbooks online, you can specify the total for the payment and link multiple invoices to it. However, there is not a place in the line item section to add the amount for each line item. Workato only supports the TxnId and TxnType. The amount per line item is supported by the QBO API. See below for the example code they give and link to their page.
Sincere apologies for not getting back to you on this sooner. The Amount in the Create Payment action is nested under the Line section, which means that you can have a different amount per line as long as you map the line source list. Do try this out and let us know if you are still facing any issues.
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