FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
FortiGate automation stitch comprises of two parts: a trigger and an action. 
There are various triggers that can be used, including a predefined schedule. 

This descrbes a way to debug the automation stitch and thus help the user to find the cause of the problem.

Debugging the automation stitch is done in command line with the following commands:

FortiGate # diag test app autod 0
1. Enable/disable log dumping
2. Show automation settings.
3. Show automation statistics.
4. Show plugin statistics.
5. Show running stitches.

These are the available options for this process, and they can provide valuable information about why the automation stitch failed to work.
For example, we can see which automation is active:

FortiGate # diag test app autod 2
csf: disabled   root:no
version:0 sync time:
total stitches activated: 1

stitch: backup
        destinations: all
        trigger: backup

        local hit: 0 relayed to: 0 relayed from: 0
                backup type:cli-script interval:0
                        delay:0 required:yes
                        script:execute backup config ftp /Backup/backup.cfg testuser testpassword

Or it is posible to see if the statistics for this process:

FortiGate # diag test app autod 4

action plugin stats:
                stats: total:0 cur:0 done:0 drop:0
                stats: total:172 cur:0 done:172 drop:0
                stats: total:0 cur:0 done:0 drop:0

Most importantly, to troubleshoot the automation stitch process, it is necessary to stop all running scripts, reset any debug that may be running, then enable log dumping and cli debug for automation stitch.
This is writing to console the commands taken once the automation stitch is triggered.

FortiGate # exec auto-script stopall
No script is running.
FortiGate # diag debug reset
FortiGate # diag test app autod 1
autod log dumping is enabled
FortiGate # diag debug cli 7
Debug messages will be on for 30 minutes.
FortiGate # diag debug enable

Now, it is possible trigger the automation in the CLI as follows (or GUI: select the automation  to test -> Test Automation Stitch).

The command line will reveal the 'behind the scenes' actions leading to the problem experienced.

For example, in this case it shows a connectivity failure (because indeed, no such IP exists on this test network):

FortiGate # exec auto-script start backup <----- In this case, the name of the script is 'backup'.

FortiGate # auto_stitch_stats()-103: Request stitch(all) statistics
0: config system auto-script
0: edit "autod.0"
0: set script "execute backup config ftp /Backup/backup.cfg testuser testpassword"
0: end
__action_cli_script_open()-182: cli script action:backup is called. svc ctx:0x6142378
accprof:super_admin script:
execute backup config ftp /Backup/backup.cfg testuser testpassword

5: execute backup config ftp /Backup/backup.cfg testuser testpassword
__cli_script_close()-122: cli script:
########## script name: autod.0 ##########

========== #1, 2021-10-25 14:32:02 ==========
FortiGate $  execute backup config ftp /Backup/backup.cfg testuser testpassword
Please wait...

Connect to ftp server ...
Send config file to ftp server via vdom root failed.
Command fail. Return code 5
__action_cli_script_close()-209: cli script action is done.

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