@kandersen-1 mbox3rdpartyid value is set from rules using the extension. In page load request given in screenshot
Is their a way to set these values in initial page load.

@pradeep_joshi20
tntid
tntid is not visible in the first request in the debugger. This is expected as @vaibhav_mathur correctly describes. I see the same behaviour across the sites I'm supporting with Target. I would evaluate this to be working as expected.
mbox3rdpartyid
If you click on the action in Launch, then how is the parameter set? Below is an example of what i'm referring to.
Here you can see the mbox3rdpartyid parameter is set with value from data element, declaredId:

And here you can see how the data element is set - in this example it is populated from a query string parameter with the same id.

when it is set in the query string it is available when the target libraries are loading. The real question is how/where your value is set from?
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