Hi @Selina Li ,
Glad to know that you are learning from databricks academy, which helps every one of us to learn more about databricks.This issue might be a temporary issue, can you please raise a ticket in the below-mentioned portal, so that the support team can track and resolve the issue ASAP .
https://help.databricks.com/s/contact-us?ReqType=training&_ga=2.107588100.762202484.1673092790-20276...
Happy learning!!
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