After first month, another person started using my Pen Name

So been a month in, an had two successful book launches. Created my author bio after book two. Found out today that someone within the past 72 hours published a book under my pen name and created their own bio. Apparently I'm competing with another of the same pen name. Is there anything I can do? I honestly feel like just continuing on and ignoring it. They published longer work than me and are undercharging for what they made so I don't feel slighted? Honestly feel like they are trying to glob onto what I already did for their own success but eh. This pen name was something I created and researched on and no one had published under the name. Going to continue but wanted to see if this is a thing that just happens sometimes.