I am not able to check challenge 3 on Add Standard Topics. What could be the issue? I am only getting one choice under RagFileUDMO(No Retriever). I had downoaded the file and uploaded.

I am not able to check challenge 3 on Add Standard Topics. What could be the issue? I am only getting one choice under RagFileUDMO(No Retriever). I had downoaded the file and uploaded. I had already activated the agent and passed the first two challenges but got stuck  on the third challenge.