Publishing Web tool that works with data on Portal for ArcGIS and using it in Web Appbuilder

[Martin1]

I am trying to publish a web tool from ModelBuilder in ArcGIS Pro. Inside my model there is (besides other things) a script. This script works with data on the same Portal that I want to publish the Webtool to. Consequently, I need to create a connection to the Portal inside the script.

gis = GIS(url="https://***/portal", username="***", password="***?", verify_cert=False)

The model works fine in ArcGIS Pro, the script does what I want, it applies some edits to data on Portal. However, when trying to publish the layer as a webtool, I always get an error message (ERROR 00068 - Script contains broken project data source -- > see attached image):

It seems that the problem is the connection to my Portal in the script. Is there any way to avoid that? I tried using a token instead of credentials, but the result is the same.

[Martin1]

This is a screenshot of the error