Parcel not delivered and company refusing refund.

My girlfriend ordered some gym clothes from jd sports last weekend and everything went smoothly until I checked the tracking on Tuesday and it states it was delivered on the Monday at 11AM however we had no parcel from jd sports all day.

We then rang jd sports who stated that Hermes had delivered the parcel to a house opposite however they have received no parcel and we are friends with them so they wouldn't keep any parcels. We also received no attempted delivery note and someone was at home all day.

We told jd sports this however they say they cannot send new stuff out or refund the money until they get proof of our signatures. This makes no sense to us as they didn't even "deliver" the parcel to our address.

Is there anything I can do? We asked to speak to a manager but they said they don't do that, apparently it's policy.

Thanks