Songs replaced by endless copies of a different song.

[EmpaDunder]

Hi, i started using Spotify around 2008-2009 ish. Ever since, (though i at one point made a new account i believe) i have kept a "main list", meaning i had thousands of not just nostalgic songs but music i will probably not find if i go searching again.

However, 95% of all the songs in the list have been replaced by in some cases 100s of copies of another song in the playlist Leaving me with a total of 200 different songs and 6000 copies of 5 different songs.

My first thought was that some of my friends had been messing around a little, but when i check the time and date it was added i can clearly see it was ages ago the song was added to the list.
Is there a way to reverse this? Though it's just music there was alot of time, effort and feelz put into this list.

TLDR; Playlist has replaced most of my songs with large amount of copies, is there a way to reverse this? It's the same on any device i use.