I published a paper in a reputable journal in 2021 December. I had proved a conjecture. Today I discovered that another author published a special case of the conjecture and published it, in another journal, in 2023.
I think it is wrong on the journal's part. Why did the Editors publish the paper when they can see that it is a special case of my paper?
Shall I write to the journal and ask them to remove the paper from their website? Or do I file a case of plagiarism against the author?
If someone can kindly help, I will be grateful.