Someone (Aさん) asks a question on a forum. Bさん provides an answer. I see the
answer as incomplete, so I correct Bさん and provide some supplementary
information. Aさん, the OP, replies to me:

> あ、本当だ。完全に見落としてました。ありがとうございます‼️

I thought that was the end of it. But then Bさん says back to me:

> 打ってなかった

I am thrown by this response. I don't know what Bさん is trying to say or if
they are displeased because I corrected them (not the first time). What does
打つ mean here? "It didn't occur to me"? What's also off about that response is
everybody is very polite on the forum, basically 敬語 all the way. Bさん too,
except in this one repsonse to me. えっため口？なんで？俺、何か悪いことした？ That's how I feel. So
what do they mean?

A little more background: it is a math question. The correct answer includes
two possibilities, and Bさん only gives a number based on one of the
possibilities. I complement their answer by showing another possible option.
CC BY-SA 4.0
2021-01-01T05:36:58.773
83401
2021-01-01T06:09:03.830
2021-01-01T06:09:03.830
30454
30454
question
meaning word-usage
What does「打ってなかった」mean here?