Bash script execution error, what could be the error?

Question

Python

I create my own action rule in fail2ban
actionban = /home/ban.sh ban <ip>

The ban.sh file itself

#!/bin/bash
/usr/bin/python3 /home/ban.py $1 $2

If you just run the ban.sh ban ip-addr file, then everything works fine.
If this rule is executed in action opnsense, then it gives an error

exec: /home/ban.sh ban <ip>
stderr: '/bin/sh: 1: Syntax error: end of file unexpected'
returned 2

The rights are exposed, it is simple ban.sh is started without any errors. What could be the problem?

Answer 1

and if
1) remove the line #! /bin/bash in general or replace with #!/bin/sh ?
2) replace the ban.sh script with ban.py - write it in python at the top of the line: #! /usr/bin/python3

Answer 2

Why run a python script from a bash script?
Run the python script right away.