error identification

The candidates complained that they had not enough time to answer all the questions in the English Paper.
I can't identify the error of this sentence.Can someone point out the mistake?

[hector51]

The candidates complained that they had not enough time to answer all the questions in the English Paper

I think this sentence should be "The candidates complained that they had not had enough time to answer all the questions in the English Paper"

Since this is reported speech,we use past perfect tense here.

My 2 cents.

[mykwyner]

I like, "...that they did not have enough..."

There are other good choices, but this is where the error is.