Double Negative

Using two negative words in the same clause (group of words) creates a double negative. 
A double negative is an incorrect usage and should be avoided. To avoid this grammatical error,

use only one negative word to express a negative idea.

Double negative: The traveler did not have no energy after the long flight.

Correct: The traveler did not have any energy after the long flight.

or

The traveler had no energy left after the long flight.

Double negative: Shakira could not hardly see in the blizzard.

Correct: Shakira could hardly see in the blizzard.

or

Shakira could barely see in the blizzard.

Double negatives are especially likely to cause problems when contractions are used.

When the word not is used in a contraction—such as isn’t, doesn’t, wouldn’t, couldn’t, don’t—the negative tends to slip by. As a result, writers and speakers may add another negative.

Double negative: Billy didn’t bring nothing with him on vacation.

Correct: Billy didn’t bring anything with him on vacation.

or

Billy brought hardly anything with him on vacation.

However, to create understatement, you can use a word with a negative prefix and another

negative word. The two most common negative prefixes are un- and -in.

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The report is not inaccurate, but no one should stake their reputation on it.