Use Mailjet Template Variables

Hey,

I have a question.
I try send email templates via mailjet - that works fine, but I try to set variables in the template and also then the keys in the scenario but it does not work, does not matter how I enter the variable in the scenario, the emails I receive only show the variabel but not the value.

Would be great if some of you could help me with that.

Here are some pictures:

Example Code given by Mailjet:
image

Template:

Scenario setup variables:
image

Input Bundle:
image

I don’t know how, I already tried several variants for the key but none of them are working:
{{var:OrderNr:“”}}
{var:OrderNr:“”}
var:OrderNr
“var:OrderNr”
OrderNr
“OrderNr”
var_OrderNr
“var_OrderNr”

Thank you for your help!!