Welcome to Nikonians,Sorry to hear about the problem.First try a second card, make sure it is listed as approved by Nikon, and see if that card will format and keep its format.If not then I would call Nikon support.Remember there is a safety feature involved in formatting and if you use the 2 button format you need to press the sequence twice, the second confirms the action.
GeorgeMy Nikonian Galleries
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