lowercase letters in Characters in Photoshop Test (23.4.2) on Mac Mini M1
Several essays, the text remains in Capital letters
In other applications, no problem
The most likely reason is that All Caps has been set as a character format. Select your text and open your Character panel from the Window menu. Across the bottom are icons for Fake Bold, Fake Italic, All Caps, Small Caps, et cetera. Turn off the All Caps button.
Note: Text must be selected when you apply formats from the Character panel.