So the iPhone 12 mini was a promising device in the iPhone 12 series, with same specs as the iPhone 12 (A14 Bionic chip, OLED display, Two camera) but in a small form factor of 5.4 inches and lesser battery. However this has not turned out to be the best iPhone for Apple, leading them to reduce / stop production in the coming months and reducing the price as well. 

Links

https://gadgets.ndtv.com/mobiles/news/iphone-12-mini-production-discontinuation-q2-2021-apple-pro-max-2365585

https://appleinsider.com/articles/21/02/04/apple-may-be-building-more-iphone-12-pro-units-to-meet-strong-demand