Why are some songs missing after Importing from a CD on Mac?

I have just tried importing a CD onto my iMac 24, there are 11 songs on the CD. I get the green tick telling me all songs have been successfully imported.

Then when I try to play on computer, 2 songs are missing. I tried importing the 2 songs on their own, same result!

I don't know what's going on.

Does anyone have any ideas, or, did I get a dodgy CD?

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