QSBS, Sec 1202 exclusions

I have two QSBS eligible blocks of stock. Both sold on the same day. One blocks purchase date provide/is eligible for  a 75% exclusion (I meet all criteria for exclusion).  When I enter that info, the applicable gain and resulting owed tax is very close to what I would expect. (I.e., 25% of the blocks gain is taxed accordingly.  The second blocks purchase date provides/is eligible for a 100% exclusion.  But when I enter the info (entry info is identical to the first block, except #of shares, cost basis and purchase date)....Turbotax applies a tax to the entire gain?? The resulting tax for this second block gain should be "0".  Meaning, my tax bill for the total gain of two sales should be just the tax bill for the first block. ( Note: I do not have any prior QSBS sales, and I am no where close to the $10mil/10x cost basis criteria).    I cannot identify what I am doing wrong.  Thank you  MTM