If redownloading music is available in your area, I recommend deleting the song from your library and redownloading it through iTunes in the Cloud.
This article will help you determine what content is available for redownloading in your area:
This article will walk you through the actual redownloading of the file:
Downloading past purchases from the App Store, iBookstore, and iTunes Store
I hope this helps! Best wishes and good luck!
Thanks for your answer and sorry for the delay of my answer
I tried the process you gave me but it didn't work. I don't see any cloud icon even if it's activated on the settings.
I am located in France and I don't understand what I have done wrong because I get this
Here a sample of my library with another track on which I have the same problem.