No feedback on expensive lost item

Recently tried to return an expensive, barely-used product. It was collected within 1 day and the Return was rejected (not within 30-day policy). Totally understand. HOWEVER, it's been 9 days of back/forth with NO update as to where the item is/when it will be returned. I have received multiple emails saying "we will provide feedback", with zero feedback. I am completely disappointed with this service. It's impossible to contact any sort of superior/manager to escalate matters this serious (lost, expensive items).