Similar to not funny, didn't laugh, not funny again is used whenever someone who has no humor tries to make a joke. It is part of the three line shut-down:

not funny again
why do you always copy me
this is all you do

, which is used when somebody copies your joke, thinking that they are being funny.

Saying not funny again instantly destroys the person trying to make a joke, rendering them completely useless for at least 10 seconds. You can also use not funny again whenever a non-humorous being tries to speak, making them get frustrated, and give up speaking to you.
Example 1:
Shail: You wanna hear a joke?
Jeffrey: Sure, but it better be good.
Shail Patel: What's 9+10?
Jeffrey: Lemme guess, 21?
Shail: No, stupid, it's 19 HAHAHAHAHAHAA
Jeffrey: Not funny again.
Shail: :(

Example 2:
Shail: Hey can you help me with-
Lawrence: Not funny again
Shail: What??? I was just asking whether-
Lawrence: Not funny again, why do you always copy me, this is all you do
Shail: *leaves*
by NotFakeNewser May 26, 2021
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