我们对这句话不是很明白，我们理解是要对合同进行不低于合同额的二倍进行投

We do not quite understand this sentence, our understanding of the contract is to be not less than twice the amount of the contract were insured. Or the two sides can agree on a minimum insurance limit. For this provision in more detail please give a clear explanation

We don't quite understand this statement, we understand that the contract is not less than twice the contract amount. Or the two parties may agree on a minimum coverage limit. Please give a more detailed and clear explanation of this provision

We don't quite understand this sentence. We understand that it is necessary to insure the contract for not less than twice the contract value. Or both parties can agree on a minimum insurance limit. Please give a more detailed and clear explanation for this clause