obtener Variables UTM delivery

Good morning,
I am trying to retrieve these variables to add them as UTM parameters in a URL from a delivery but unfortunately when previewing they are always empty except the transaction ID.

I am using them like this inside the HTM Context.
<p>Message type: <%= delivery.messageType %></p>
<p>Operation ID: <%= delivery.operation_id %></p>
<p>Operation label: <%= delivery.operation.label %></p>
<p>Internal name of operation: <%= delivery.operation.internalName %></p>

The idea is to somehow fill in these variables.
(utm_medium ,utm_source ,utm_campaign,utm_content,utm_term)
to be able to concatenate them in my url, can you help me?

Thank you!