Somebody may have launched or promoted a site with a very similar name to yours or maybe the same name in another extension.
Put the keywords into Google News and Google Search to see if you find anything new, you can also check at places like eurodns.com to see if its registered in other extensions, if it is, take a look and see what they're doing with it and who owns it.
Also, If you check your domain on whois.sc it will show you a few similar domains to yours in the bottom right hand corner of the page, from there you can check who owns it.
They're usually the first thing I do when I see any strange surges in traffic.
If you post the name maybe it'll be a bit easier to find out why ?
Good luck and welcome to NamePros . :tu:
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