People who program computers make mistakes.  You can try calling IRS and demanding perfection, but you won't get it.  You will just listen to a lot of music on hold, then take time away from the few remaining staff who want to help people who have real problems.  You seem to have some unresolved issues about the loss of your sister, and we all share our sympathy.  But if you want an apology, contact your member of Congress and point out that it's false economy to fire programmers when more are needed, with better morale, to prevent such mistakes.