While publishing to a hosted feature layer to ArcGIS Online (user is a creator/publisher or administrator, both with the same result), the following are the errors we get with different publishing scenarios:
- trying to publish with ArcGIS Pro (2.4.2) failed with this log file:

We also tried with ArcMap with the same result.
- trying to upload (add item) a zipped shape file and publish it as hosted layer:

- trying to create a layer from a template within AGOL like


This doesn’t bring an error message but just turns grey for a second or two and goes back to the blueish version but doesn’t do anything in the end.
This is a newly setup subscription with many users and many credits so it can’t be a credits issue.
The health status also doesn’t show any issues from the system.
Any ideas?