Keyboard not working

Hi commuity
I am a noob, and this is a noob question…

OS (e.g. Win10): Win 10
PsychoPy version (e.g. 1.84.x): 1.90.1
Standard Standalone? (y/n) If not then what?:yes
**What are you trying to achieve?:**add response key to a routine

What did you try to make it work?:
try to add [‘a’,‘l’] as “Allowed keys”
What specifically went wrong when you tried that?:
During the experiment, when ‘a’ press a and ‘l’ on the keyborad, nothing happened.
However, when i try to use other keys e.g., [‘space’, ‘1’,‘2’…etc] as “Allowed keys” they works fine.
In fact, all letter keys are not working, but all non-letter keys are working.
But i really want to use letter keys…

Include pasted full error message if possible. “That didn’t work” is not enough information.
There is no error message…

Is the caps lock on?

Is your keyboard setting in your operating system set to an English (e.g. UK, US, Australian, etc) option (I guess so, if you are able to type those characters into PsychoPy’s dialog box).

Thanks,
but i think it is not the caps lock…I will use [“lalt”,“rlat”] for now.