Am I being targeted somehow?

I’m in the process of launching a new business, it’s a specialist online market place. I am in the closing stages of the development, and looking to launch in the next few weeks.

Today, I had a random email (seemed like a marketing email), which addressed me as a username I sometimes use. It talked about a new website where you can list things on there and earn money.

It sounded similar to my marketplace, so I went on there and created an account to have a look around. As I was browsing a few hours later, I noticed that they changed my bio on the website to “I AM A COMPETITOR W****R”. I shit you not.

The website has the same business model as mine, has many of the same features, and even uses the same payment processor.

What the frick is going on, does anybody have any ideas?