RETURN ITEMS STILL NOT SENT BACK TO SHEIN SINCE JANUARY

These people collected my items in January to send back to Shein for a refund. I have been calling without any help ,no communication . The refund is been cancelled they have my items ,NO REFUND The parcel have not reached its destination ,they keep saying its in their warehouse . I am so drained and tired, even their watsap is useless They are ******