My dad couldn't vote

So this all happened on election day. Being the outrageous subversive that I am I voted early just after the polls opened. This meant braving the lone nutter standing out front screaming about saving our children from the perverts. I haven't the faintest idea what that was about since I recall zero ballot propositions regarding perverts and children. But anyways I got myself inside where I stood up against the death glare of the elderly poll workers wondering on the inside why anyone under the age of 50 can vote. They asked for my address and I told them, they asked if I was Travis, I affirmed. They asked me to sign by my name.



Here is the important thing. As I did I saw my dad's name above mine, sans signature because he wasn't going to vote until later that day. At the time I thought nothing of it. Same old, same old.



I went and did the thing Republicans hate: voted. Slid my ballot into the scantron machine and went about my day.



Later that day my dad tried to vote. But.....they couldn't find him. They said he wasn't on the rolls. My dad has voted in every election since 1966 except...this time he wasn't there.



But he was there. I saw that he was there when I voted. I remember it pretty distinctly. I didn't find out about this until that night when he came home. By then it was too late to do anything.



How was he on the voter rolls in the morning but not later that evening?