The BOT worked when I first installed A47 (2/12), but something has happened since then. Anyway the main working of the BOT is two scripts:
OxSay
______________________________________
< You are fairminded, just and loving. >
--------------------------------------
\ ,-----._
. \ . ,' `-.__,------._
// \ __\\' `-.
(( _____-'___)) |
`:='/ (alf_/ |
`.=| |=' |
|) O | \
| | /\ \
| / . / \ \
| .-..__ ___ .--' \ |\ \ |
|o o | ``--.___. / `-' \ \\ \ |
`--'' ' .' / / | | | | \
| | / / | | | mmm
| || | | /| |
( .' \ \ || | |
| | \ \ // / /
| | \ \ || |_
/ | |_/ /_|
/__/

And cowsay.ini:
; mpipost.ini - MUTIL BBS Ad Poster
; to FSX_BOT Now index 6

[General]

PostTextFiles = true

; ==========================================================================

[PostTextFiles]

; Total number of text files to be posted. For each file there needs to

; be a file definition as show below.

totalfiles = 1

; This defines one file which will be posted to the message base. Each
; file should be prefixed with file# where # is a number from 1 to
; totalfiles.
;
; The delfile option (if true) will remove the filename after the message
; is posted. The baseidx is the permanent index of the message base to
; post the message into (shown as Index at the top of the message base
; editor in Mystic's configuration. Address is the echomail destination
; address

file1_name = OxSay
file1_baseidx = 6
file1_from = Mystic Pi BBS
file1_to = All
file1_subj = Mystic Pi Year of the Ox
file1_addr = 21:1/145
file1_delfile = false

; ==========================================================================

Any idea why it no longer posts to FSX_BOT like it should?

--- Mystic BBS v1.12 A47 2021/02/12 (Raspberry Pi/32)
* Origin: Mystic Pi BBS bcw142.zapto.org:23 (21:1/145)