This can happen in random circumstances. A long time ago Amazon did not allow me to ship to my home address. By trial and error I found out that if I changed a specific o in my address to something else, it suddenly worked. There are no special reserved or offensive words in the address, I've never found out why this was. It had been fixed since.

Also I own a domain name with a catch all email address. If I sign up for websites, I often use the company name in the email adress to track leaks or spam. They sometimes don't allow this.