Hello Andrew, and welcome to the friendly Camera Labs forum!
To enjoy your stay here please have a look at the house-rules
With respect to your problem, this is a built-in limit for continuous shooting (one single take). It's written in the manual in the chapter "maximum recording time".
But naturally you can record until you reach the limit of your mem-card in multiple takes.
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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