Meaning of "we mustn't leave it so long next time"

[Satke]

Business Idiom in English, Intermediate level

ESL/EFL Test #130 "Way of saying goodbye", question 8

It's been great meeting up again and we mustn't ......... it so long next time.

(a) leave
(b) take
(c) wait
(d) lose

Business Idiom in English, Intermediate level

ESL/EFL Test #130 "Way of saying goodbye", answer 8

It's been great meeting up again and we mustn't leave it so long next time.

Correct answer: (a) leave

Your answer was: incorrect
It's been great meeting up again and we mustn't take it so long next time.
_________________________

Can you please explain meaning of the last part?

Thanks
Satke

[Mister Micawber]

.
We should meet sooner next time (not leave our next meeting until such a long time in the future).
.
_________________
Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mr. Micawber