I can't load any lakehouse or warehouse SQL endpoint in Fabric. It waits about a minute, not loading anything, and then shows the error message below. I've had this happen for the past week with no solution. Querying from SSMS is very slow and queries time out as well.
Have you made any changes in the meantime? If you connect directly to the data source, can you load the data? If you recreate a lakehouse using that data source and then load the data from the lakehouse, will you still have this problem?