不 is usually used as a negative adverb in a sentence. It also has another very important use that it can form set phrases in the form of 不_不_(ABAC).
There are two cases for this use of 不
不 can convert a two-character compound to a set phrase
In this case, the two-character compounds are must be existing words and have fixed meanings, that is to say, you can find them in a dictionary.
尴尬 → 不尴不尬
言语 → 不言不语
明白 → 不明不白
上下 → 不上不下
阴阳 → 不阴不阳
知觉 → 不知不觉
骄躁 → 不骄不躁
理睬 → 不理不睬
偏倚 → 不偏不倚
痛痒 → 不痛不痒
声响 → 不声不响
日月 → 不日不月
聋哑→ 不聋不哑
文武 → 不文不武
折扣 → 不折不扣
男女 → 不男不女
慌忙 → 不慌不忙
古今 → 不古不今
茶饭 → 不茶不饭
You can see the two characters in each compound can be synonyms, antonyms or two words having closely related meanings.
不 can convert two characters that can be either a pair of synonyms or antonyms to a set phrase
In this case, the two characters are not an existing word, in other words, you can’t find them together as a word in a dictionary, for example, 轮类，管顾，识知，闻问，etc
伦，类 → 不伦不类
管，顾→ 不管不顾
识，知→ 不识不知
悱，发→ 不悱不发
愤，启→ 不愤不启
丰，杀→ 不丰不杀
卑，亢→ 不卑不亢
哼，哈→ 不哼不哈
即，离→ 不即不离
疾，徐→ 不疾不徐
依，饶→ 不依不饶
夷，惠→ 不夷不惠
吐，茹→ 不吐不茹
生，灭→ 不生不灭
偏，党→ 不偏不党
蔓，枝→ 不蔓不枝
愧，作→ 不愧不作
郎，秀→ 不郎不秀
稂，莠→ 不稂不莠
稼，穑→ 不稼不穑
破，立→ 不破不立
屈，挠→ 不屈不挠
三，四→ 不三不四
Check all these words for their pronunciations and meanings on 百度汉语, 百度翻译 or 汉典.