The trivial mistake clearly shows that a good amount of time was not invested in debugging the code. I would advise you to do the same instead of posting it on the forum straightaway.
In case you need,
your ACfied code
#include <iostream>
using namespace std;
int main() {
int n;
cin >> n;
bool five = n % 5 == 0, eleven = n % 11 == 0;
if(n < 5) cout << "NONE";
else if(five && eleven)cout << "BOTH";
else if(five || eleven ) cout << "ONE";
else cout << "NONE";
return 0;
}