Connie's first Billboard Number One was Lipstick On Your Collar and her final one was Vacation!
For awhile the only other artists who had more top ten hits were Elvis and The Beatles.
I think you mean first and last top ten tunes. Lipstick peaked in Billboard at #5 in ‘59 and Vacation peaked at #9 in 1962. But what a run she had over 3 years!
Her Billboard #1s were:
Everybody’s Somebody’s Fool 1960 (as a b-side!)
My Heart Has a Mind of its Own 1960
Don’t Break the Heart that Loves You 1962
After 1963 she never even hit the top 20 again.