Rare collection book?

Pleasure

I have a complete set book of Franklin and Kennedy halves with on exception that is driving me nuts and I think the coin it's calling for has never been minted. The book is a Whitman 9221. It combines Franklin halves from 1948-1963, then begins with Kennedy in 1964. It calls for a Kennedy 64, then a 64-D, A Kennedy 65, Then a Kennedy 65-D. There is no 65-D ever minted, that I can find. The rest of that page and the next are filled with blank holes as well as the next page. Please help!
Thank you in advance!!