Having a problem running a script from the terminal

Technical Support for Routers
1

First, I set the file as executable, and then execute it.

root@GL-E750:/# chmod +x ./airplane_mode.sh
root@GL-E750:/# ./airplane_mode.sh

Then I receive an error message:

-ash: ./airplane_mode.sh: not found

The contents of the bash script are as follows:

#!/bin/bash
SSID=$1
if [ iw dev wlan0 scan | grep "$SSID" ];
then
echo "Internet nearby"
else
echo "Internet not nearby"
fi

What could be causing my issue?

Thank you.

2

Change #!/bin/bash to #!/bin/sh

3

I did this, now I'm getting a completely different error message:

sh: missing ]
grep: ]: No such file or directory
Internet not nearby

Do I have a syntax error?