Please state in which country your phrase tends to be used, what the phrase is, and what it should be.
Example:
In America, recently came across “back-petal”, instead of back-pedal. Also, still hearing “for all intensive purposes” instead of “for all intents and purposes”.
What do you base that on?
According to the pronunciations on Wiktionary, nitch is Californian
https://www.merriam-webster.com/dictionary/niche