+1
Do try the store management. You can also try emailing upper management. Aim as high up the management food chain as possible. The CEO is Ryan McDonnell and you can email him at ryan.mcdonnell@lidl.co.uk. Whilst he is not likely to deal with it, he will have one of his upper management minions sort it for you.
However, the location is too vague on the NtK as it will simply say "Lidl Ashford", even though we've not seen it. This is another PoFA failure.
Is it:
Lidl, Stanwell Rd, Shepperton, Stanwell, Ashford TW15 3DT;
or is it
Lidl, 25 New St, Ashford TN24 8TN.