[Konstantinos]

fclose function crashes the server. This happens when an invalid file handle (trying to close a not opened file) is used.

Let me show you the wrong and correct way.

pawn Код:

// WRONG WAY:
new File: fhandle = fopen(...);
...
fclose(fhandle);

and

pawn Код:

// CORRECT WAY:
new File: fhandle = fopen(...);
if (fhandle) // valid file handle
{
    ...
    fclose(fhandle);
    // call file functions (fopen is excluded) ONLY if valid file handle
}

So find LoadBancoJob public function and fix the code or if you cannot, at least post this function.