I agree that not adding a UA-code in the widgets is probably the cause. Not sure if this has to do with your studio version.
In the below link you can find an example of the js code for your page/flow and the code you have to add to your index first.
See also: https://developers.google.com/tag-platform/tag-manager/web
btw, there are great extentions ‘Datalayer Checker’ or ‘Dataslayer’ for your browser to check and test the data is being sent in your browser console.