Why bot server response turn slow(hang) sometimes?

[fancyoung]

I'm design a long flow bot, user should go through nodes one by one.

I find sometimes, when user selected an answer, the server response it very slow (happened on different nodes, may be 10+ operations will have 1 slow response).

Sometimes, the response is slow, but can turn working after 10 seconds. Sometimes, there is no feedback, so user can't continue their flow.

I have two questions:

1. does other have this problem, how to solve it?
2. if we can't fix it which cause flow break, any suggest practice to let user continue the flow?