I am trying to use a global parameterized dataset as a source and as a sink in my data flow inside my data factory. But the test connection fails in my data flow. It only works if I don't use parameters. It works if I change the 'item().name' to the file's name.

Workaround:

In your scenario, since you have a parameterized dataset in dataflow, when using dataflow activity in Pipeline, you will be prompted to provide values to those properties. Here you can mention that Global Parameter.