Received 6174-A from IRS

First of all, It is my understanding that the order of these letters go in the order of a 6174 first, then the 6174-A and finally a 6173. Although I never recall receiving a 6174 to begin with; I am having a hard time understanding why I received this letter from the IRS to begin with. I have no business in crypto-currency currently and haven't had any actual trading other than the dabbling in it from December 2017 to March 2018 and never exceeded $400. I even went through the hassle of accessing these old accounts I could remember. Accounts such as Binance US (Which is no longer supported in the USA), Poloniex (shutdown last year) and finally Coinbase. 

None of these accounts I got into have any trading currently let alone any holdings in them other than Coinbase which to my surprise has a very minuet amount of LTC but its only 0.00000002 which shows only worth $0.01.

I'm just really confused on why I am getting this letter when I haven't bought, sold and/or used virtual currency for transactions in over 7 years. If someone could please shed some light on this or give me some answers of relief, I'd be happy.