This is happening because WHFIT reporting treats certain distributions from trusts differently than regular dividends. These small monthly amounts are likely return of capital distributions and not actual sales of shares. For the "date acquired" field, you should use the date shown on each specific transaction line on your 1099-B. Don't use your original purchase date, as the IRS expects these transactions to be reported as short-term.
This type of reporting changed recently, which is why you haven't seen it on previous returns.
If you have any doubts, you can confirm with your brokerage the nature of these WHFIT transactions on your 1099-B.
