Hey... So I found something new again. This might be a big help... or it might not, I'm not sure.
This issue
might be connected to banned or restricted mappers. This leads me to create a new theory about this subject. We know that this problem is connected to seemingly duplicated maps which
shouldn't exist since the game checks if you are reuploading another player's map. My new theory is that there is a chance that when a mapper is banned or restricted, the game allows the reuploading of their maps which, in turn, creates the maps with this problem. This might be because the game cannot tell if the banned mapper exists or not since that mapper no longer has a profile.
Here are some examples in which my theory would make sense:
This map
https://osu.ppy.sh/b/115148 is being wrongly recognized as this map
https://osu.ppy.sh/b/263092. Both maps say that they were created by the mapper Furawa. The ranked mapset page leads to Furawa's user page
https://osu.ppy.sh/u/102682 while the unranked mapset leads to a broken profile
https://osu.ppy.sh/u/1628491.
This map
https://osu.ppy.sh/b/391522 is being wrongly recognized as this map
https://osu.ppy.sh/b/533497. The ranked mapset was created by Sekai-nyan and leads to his profile
https://osu.ppy.sh/u/700887 while the unranked mapset was created by Cuked and leads to a broken profile
https://osu.ppy.sh/u/5148547.
Not all of the maps with this problem work exactly like this, but that makes me think that the other mapsets that have this problem were created when the original mappers was restricted or banned. Those mappers would then go on to be unrestricted or unbanned later.
I hope that someone on the support team or dev team could at least look into this new theory a tiny bit. I would really appreciate it. In the meantime, I'm going to message Sieg to see if he has been restricted within the last year because his map
https://osu.ppy.sh/s/362500 was the most recent map to have this problem. The map no longer has this problem because the conflicting beatmap has been deleted, but it will still be worth talking to Sieg about it anyway.
Thanks for reading!
EDIT: Nevermind, Sieg has disabled private message receipt. If anybody who knows him could ask him whether he has been restricted or banned for a time within the last year
OR if he reuploaded another map for the base of this map
https://osu.ppy.sh/s/362500. That would be great, thanks.