He was just saying that perhaps he should have phoned before dropping in and I said that I thought perhaps he should have, too.
7 seconds sound clip from the Desk Set (1957) movie soundboard.
You can hear this line at 00:51:44 in the Blu-ray version of the movie.
Quote context
[...]
- I'll, uh... I'll get another cup. Won't be a second.
- I, uh, suppose I should have called first.
- Well, it never occurred to me that anybody'd be here.
- Still, uh... Still raining out?
[...]