Thank you! Replacing ‘category’ for ‘categories’ indeed fixes the ask query. However, even with this change, the askargs query does not work as expected. There is a particular server I want to interact with, but this server returns HTTP 500 errors on ask queries containing printouts. Askargs queries seem to work fine, except for the problem with missing category printouts.
By the way, how does one perform logical OR operations between conditions in an askargs query?
The administrator of the server that was having issues with ask queries was able to fix the issue. There was a missing package ‘php-mbstring’ causing the HTTP 500 errors. Now my ask queries are working perfectly.