so many duplicate downloads

Why does apple CONSTANTLY keep redownloading the same songs? I have one song that has duplicated 4 times, so I have 5 of the same version of one song. If I delete it, it won't delete, it just 'moves' to the recycle bin but never leaves the library. It has the download icon next to it. I have OVER 2000 songs each having multiple duplicates. I'd have to click on over 5000 different songs because apple keeps doing this and every answer I've found online provides no help. No, I don't have automatic downloads on. Yes, I know how to find duplicate songs from the file menu. Is there any way for apple to NOT continue doing this? I believe the culprit is every time I plug my phone in, new songs are added but then at the end it duplicates like 300 songs each time. Also, anyway to actually get the duplicates to delete and not just stay present in my songs folder with the download icon beside it? My ipod is running low because of the mounds of extra songs...