@SimonATS Thank you for your response! I added the dynamic value of the Sender but it is the same I putted there in the first place. I've added the same value for 'In the name of' also to the actions: Upload and Create agreement as in the picture below:

The sender is the owner of the account and "I'm the robot". Please advize on how to authorize as everything else I've tried.
Thank you so much!
Actually forget about all that. You are using the wrong action. You want to use the 'get Pdf from a signed agreement'. Even if the agreement has not been signed it still should give you a pdf.
The document id in the 'Get document from the agreement', is not the same ID that is created when uploaded my doc before creating the agreement. To use this action you first need to add the action "Get a list of all the document IDs from an agreement"
As an agreement can have multiple document, this action returns an array of IDS. So if you are just after the combined PDF, use the 'get Pdf from a signed agreement'. which only needs the agreementID.
Overall though, unless you have a specifc need for the unsigned agreement, it's better to use a second flow to check the staus and grab the signed PDF. Create a new flow and use the Sign trigger 'When an agreement workflow is completed'.