It used to be that InDesign had no trouble when a character style ran more than one line. From some time, including InDesign 16.2.1, if a character style is applied to a string of text that starts on one line and continues to the next line, for example the last few words on a line and the first few words on the next line, InDesign will force all the text with that Character Style onto the next line, and space on the text on the previous line to span the entire line.
However, if you don't use a Character Style say to apply oblique to the text, and apply oblique to the text manually using the Font from the Type menu, then there is no problem.