Keyboard Shortcuts for Layer Blend Modes Not Working (intermittently)

[cab993]

The keyboard shortcuts for layer blend modes are---intermittently---not working.  I select a tool like the marquee tool and hit, for example, the T key (for the saturation blend mode).  Sometimes it works and changes the layer blend mode; most of the time it does not work.  I have been unable to correlate its working/not working with anything I'm doing.

I an on a 27" iMac running latest versions: PS (22.4.1) MacOS (11.3.1) .

Insights appreciated!

[cab993]

I should have said I hit the alt and shift keys and the shortcut key!

[cab993]

option, not alt!