If you have a complaint about your lawyer then you can contact the Legal Services Commissioner. There is a form on their website which you can use to complain. This is only for complaints about your lawyer. To complain about the courts or court staff, you need to do something else.
It can help to try and talk about the problem with the lawyer or the people they work for. Sometimes this can fix the problem without you having to put in a formal complaint. But if you are not comfortable doing this, or it doesn’t work, you have the right to contact the Legal Services Commissioner.