Hi,
ebay won't do anything I'm afraid. All you can do is grovel to the buyer and apologise, then keep your fingers crossed they don't leave a neg/trashed ratings, nor report for seller non performance.
Mistakes do happen, so hopefully they'll be understanding.
However, they're unlikely to be happy to see you have already relisted and at 99p too. You should always start your listings at the minimum price you are prepared to accept.
Incidentlaly, you need to change the method of postage on your £85 boots to Special Delivery Next Day or a courier with on-line tracking. Normal post and Recorded only covers for up to £46 in the event of loss/damage through R.M.

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