MMonit stop error

Hello,

I'm trying to stop MMonit (the collector app) using command shown in the
documentation but I'm always hitting an error:

mmonit@myhost:~$ /usr/share/mmonit/bin/mmonit -d stop
AssertException: Cannot stop the mmonit process (1) -- Operation not
permitted
 raised in OS_finalize at src/system/OS.c:209
Aborted

with mmonit start as user "mmonit" with command from another console (in
fact System.D):

mmonit@myhost:~$ /usr/share/mmonit/mmonit/bin/mmonit -i

Best regards.