Refund & parcel lost

I’ve completed a return online on the 29th June. Received an sms to say buffalo will collect within 2 days. They only collected on 30July. Now on the app it says buffalo will be collecting , the driver took my return parcel & didn’t update it on the system on there side. I’ve called numerous times, sent emails only to be told that it’s escalated to management but nothing happens. No Response on whatsapp. Terrible service received. My parcel is lost somewhere & no one can assist. Up to date I’m still waiting for my refund from buffalo logistics