Merging an already split invoice line

Summary:

I have an invoice line for an asset that has multiple quantities for the same item. I would like to split the the line and then merge one of the lines to another line to make up the asset. Is there a way to do this?

The error I receive after I split and try to merge is the following:

You can't merge source lines because they can be merged only when the queue status is New or On Hold for source lines that haven't been split previously. (FA-645645)

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