Linux Bash Shell Script Error: cannot execute: required file not found

I have two similar scripts with different names. One works fine but other throws error. Can anyone please tell me what is the issue? This is my test.sh scripts which works fine

[nnice@myhost Scripts]$ cat test.sh 
#!/bin/bash
function fun {     
        echo "hostname"
}
fun 
[nnice@myhost Scripts]$ ./test.sh 
myhost.fedora

Here is my another script demo.sh but it throws error

[nnice@myhost Scripts]$ cat demo.sh 
#!/bin/bash
function fun { 
	echo "hostname"
}
fun
[nnice@myhost Scripts]$ ./demo.sh 
bash: ./demo.sh: cannot execute: required file not found

Both scripts having the same permissions

[nnice@myhost Scripts]$ ll test.sh 
-rwxr-xr-x. 1 nnice nnice 65 Oct 21 10:47 test.sh
[nnice@myhost Scripts]$ ll demo.sh 
-rwxr-xr-x. 1 nnice nnice 58 Oct 21 10:46 demo.sh