It is most likely that the broker put out a corrected statement which changed the amounts the IRS has as opposed to you making an entry after filing.
Did they send a CP2000 ? If so they should show 2 columns ... what you reported and what was reported by others. Seek assistance as mentioned before since IRS notices can be confusing. Start by looking at one piece and see if you can figure it out ... it will be the key to the rest of the items.
