Get your taxes done using TurboTax

Just received same form 3531 with  copy of my 2019 taxes I filed online. Don't understand what this is all about as I followed all the indications Turbo Tax gave me and all was supposed to have been in order. I tried a search in the IRS web site putting Form 3531 on the search bar but it resulted on no such items. Wonder if this is some type of phishing...