Working with QB fields and static text in JSON body

I am working with an API call in a pipeline and trying to update the JSON body to include the value in a QB field along with some of the static text in the JSON body provided by the third party's API.  Specifically, I have a line in the JSON Similar to this:

"emailSubject":  "Static Text",

I am trying to change it to something like this:

"emailSubject":  "{{a.qb_field}} Static Text",

When the pipeline runs the output is just the Static Text.

What do I need to do to include the QB field?

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Paul Peterson
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