Why would I be seeing IND-524 as a reject code if my DOB is correct on all forms? I've filed taxes for years now manually, so I know the SSA has my correct birthdate.

I have seen a lot people answer the question 'how do I fix the IND-524 error' with 'call SSA they probably have the wrong birthdate'.  Which I can do, I just don't know how that can be if I've always filed with my correct birthday in years past.  Wouldn't the SSA or IRS have either brought this to my attention or corrected the database by now?  And if so, what else could be causing this error?