According to doveadm-stats(1),

    "doveadm stats reset" is used to reset statistics

In fact, that does not work:

# doveadm stats reset; echo $?

usage: doveadm [-Dv] [-f <formatter>] stats <command> [<args>]
  add          [--description <string>] [--exporter <name> [--exporter-include <fields>]] [--fields <fields>] [--group-by <fields>] <name> <filter>
  dump         [-s <stats socket path>] [-r] [-f <fields>]
  remove       <name>
64

Likely a misalignment between code and manual page.

Best regards,
    g1