United Debt Services Sent 2 Pink Letters Demanding Contact

I received 1 letter that says it's the "second attempt to contact" me and that I should "Please contact our office immediately at 1-888-728-1322 regarding the adjustment of your credit accounts." This is after I have excellent credit and no outstanding debt or mortgage of any kind so I knew it was a scam. There is a warning on the letter that says "***Fairlure to Call*** Failure to call and make your minimum monthly payments will likely result in interest accruing on your unsecured credit balances at an unreasonable rate." This is definitely a rogue fraud/scam letter so they can sign you up for some services and charge you a massive fee. Beware, I'm sure they also take your bank account information when you call them DON'T GIVE THESE PEOPLE ANY INFORMATION AND THROW AWAY THIS LETTER. Save yourself. Hoping my report saves someone from undue stress.