Dispute i never had

I app**** for a loan at old mutual last year and upon my application I asked if I could pay it off earlier than the loan term and was told that yes I could do that, so I went ahead and paid it off earlier and now when I apply for a loan again they say I had a dispute and I never had a dispute with them obviously this would affect me getting any credit with them, but what I would like to know is that how is it a dispute to settle your loan before the loan term ends and if I was told I could do this.