hello.
i had this issue for awhile, but thanks God, i found a workarround for it.
when nvda keyes dont work, do the following.
1. press nvda plus q.
2. nvda exit dialog options are in the background.
3. press alt plus tab to find the dialog box.
4. press scape to close it.
in normal cases, when you press nvda plus q, nvda dialog box is
available and you can navigate immediately instead of using alt tab.

--
By God,
were I given all the seven heavens
with all they contain
in order that
I may disobey God
by depriving an ant
from the husk of a grain of barley,
I would not do it.
imam ali