Binding single file in Singularity apptainer

Question

I want to bind a single .json file to my apptainer container instead of binding the directory in which the .json file lies. However, when I try to bind the file like this:

--bind /PATH/config.json:/mnt/cfg_path

my program does not see the file, but only the path /mnt/cfg_path/. Is there any way to bind a single file, or do I have to put the file in a directory first and then bind the entire directory?

Thanks in advance!