Spark Connector Issue

I tried myself now, and I am getting the following error:

Request to read failed. Reason - HTTP request forbidden.
com.microsoft.spark.fabric.tds.error.FabricSparkTDSInternalAuthError: HTTP request forbidden.

So I am not able to use it myself either.
But to be honest I don't have experience with Scala, so perhaps I did something wrong in my code, I don't know. I tried to follow this page: Spark connector for Microsoft Fabric Synapse Data Warehouse - Microsoft Fabric | Microsoft Learn

I used this code:

Cell 1 (runs fine)

%%spark
import com.microsoft.spark.fabric.tds.implicits.read.FabricSparkTDSImplicits._
import org.apache.spark.sql.functions._

Cell 2 (gives the error when I run this cell)

%%spark
val df = spark.read.synapsesql("TestWarehouse.dbo.customer_dimension")

I also tried this

Cell 3 (gives the same error when I run this cell)

%%spark
import com.microsoft.spark.fabric.Constants
val df = spark.read.option(Constants.WorkspaceId, "550e8400-e29b-41d4-a716-446655440000").synapsesql("testwarehouse.dbo.customer_dimension")

This is my table in the Fabric Warehouse. It's in the same workspace as the Lakehouse which is the Default lakehouse of my Notebook.

So this is the table I am trying to read in a Notebook by using the Spark connector for Microsoft Fabric Synapse Data Warehouse, but I am getting the error message as mentioned above.

I am the user who created (and therefore also admin) of the workspace, the lakehouse and the warehouse.