Evri complaint: parcel has not been delivered and I am getting no support

I have attempted to return an item to a company to get a refund so I have posted the item via Evri on the 2nd of March 2026. The parcel should have arrived with the company in 3-5 business days but it remained stuck at the depot for a week. I have contacted Evri via the chat bot and a customer support has emailed me to say the parcel has been located and would be sent soon. This was on the 11th March 2026. Since then the parcel remains at the depot and has not been delivered. I’ve tried contacting someone by replying to the emails sent by the customer service team but have got no response and the chat bot or phone numbers does not give me the option to try contacting someone to discuss, it just tells me that as the parcel is over 12 days late, to or refund the buyer. I am not selling an item and sending it on, I am returning an item and therefore need this delivered to get the refund. I’ve had no ation the parcels been lost but nothing to indicate it’s being delivered soon. I want to make a complaint as the parcel appears to have been lost and I cannot get through to anyone at Evri to find a solution or discuss claiming compensation.