Nadi or Nandi

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Nadi or Nandi

On arrival in Fiji, many years ago, the pronunciation of Nadi was very carefully explained to me as (Nandi).

My question is: when was it changed to Nadi as I am now hearing it being pronounced by various news and talk show presenters? Am I the only one who notices this?

If I was to say it this way, my Fijian friends would very soon correct me.

It grates.