Nothing is wrong with your system, you're just using the wrong path to env. The most common default location of the env binary is in /usr/bin and not /bin:

$ type env
env is /usr/bin/env

So, your script is telling your system to use /bin/env, which doesn't exist, and that's why you're getting that error. Simply change to the right shebang and you should be fine:

#!/usr/bin/env bash

Nothing is wrong with your system, you're just using the wrong path to env. On Linux systems, at least, the env binary is normally in /usr/bin and not /bin:

$ type env
env is /usr/bin/env

So, your script is telling your system to use /bin/env, which doesn't exist, and that's why you're getting that error. Simply change to the right shebang and you should be fine:

#!/usr/bin/env bash

Nothing is wrong with your system, you're just using the wrong path to env. The default location of the env binary is in /usr/bin and not /bin:

$ type env
env is /usr/bin/env

So, your script is telling your system to use /bin/env, which doesn't exist, and that's why you're getting that error. Simply change to the right shebang and you should be fine:

#!/usr/bin/env bash

Nothing is wrong with your system, you're just using the wrong path to env. The most common default location of the env binary is in /usr/bin and not /bin:

$ type env
env is /usr/bin/env

So, your script is telling your system to use /bin/env, which doesn't exist, and that's why you're getting that error. Simply change to the right shebang and you should be fine:

#!/usr/bin/env bash