Sometimes text properties appear to get locked out. Say I put 3 lines of text in one layer. Then I make each line a different size font. From there I may want to adjust kerning on one line and baseline on another. Kerning may not allow any changes. Baseline might start affecting all 3 lines rather than the single highlighted line.
If I back out of that layer, click another layer, and then go back to the text layer, I can make a few changes that I want until the problem pops up again, which is frequent.