Question

If you will not pay the money the contract will be cancelled. (Correct he sentence)

Answer 1

The right sentence is ‘if you don’t pay the money, the contract will be cancelled.’

Here the syntax of the sentence is not accurate according English grammar.

When a sentence is started with ‘if’, the second clause of the sentence either will be joined by ‘then’ or there will be a comma between the primary clause and the relative clause.

Answer 2

If you do not pay the money, the contract will be cancelled.

The word “will” cannot be used in the above statement. Only “do” can be used because it is a compulsory action, if not the consequences should be faced by the person who did not do the compulsory action.

The verb “do” is used when there is a compulsory condition to be handled by the person.