Prune older file than a given age

I tried suricatactl filestore prune -d /home/yellow/suricata/filestore/ -n -v -age 2020.5.23
But it’s wrong :
suricatactl: error: unrecognized arguments: -age 2020.5.23
I find
But I still don’t know how to give the AGE.
could someboby give an example?Thank you.

Age is specified as an absolute number of seconds, minutes, hours or days.

 suricatactl filestore prune --help
usage: suricatactl filestore prune [-h] -d DIRECTORY [--age AGE] [-n] [-v]

optional arguments:
  -h, --help            show this help message and exit
  -n, --dry-run         only print what would happen
  -v, --verbose         increase verbosity
  -q, --quiet           be quiet, log warnings and errors only

required arguments:
  -d DIRECTORY, --directory DIRECTORY
                        filestore directory
  --age AGE             prune files older than age, units: s, m, h, d

I tried --age not -age,Thank you very much.