Format Painter Doesn't Work

[parastichopis]

(Using both the latest Excel release (2019?) and libraries with legacy releases) I have some music track time lengths that are in the format 5:43 (h:mm), but another column displays 5:43:00 AM. So I used both the Format, Number, Custom, h:mm option on the cells that showed the AM designation but it won't get rid of the AM. If I select the cell with the formatting I want, then selected the Format Painter, then apply it to the cell whose formatting I want to change to it either converts the time into a decimal out to 2 places, or it won't get rid of the AM.