You must report this incident again to your manager - you may not trust your manager but you must give him the benefit of the doubt. Your manager did deal with the issue when you first raised it, he may well dismiss the person this time.
If this does not solve the issue then you may need to take it further.
You must never believe what you do is simply interferingm you are not - and NEVER ignore this behaviour.
Good luck....you will be doing the right thing....stick with it!!!
