If a unilateral error is caused by fraud or misrepresentation, the contract may be cancelled for the party who made the contract error. In simple terms: if „A“ creates such situations and performs such activities to deceive „B“ and „B,“ he also made a mistake as a result of A`s complaint and entered into a contract with „A“. Then the contract is cancelled at the choice of „B.“ Illustration: Lady found a stone and sold it as topaz for 1 dollar ($25 today). It was an uncut rough diamond valued at $700 ($17,000 today). The contract is not cancelled. There was no error because neither party knew what the stone was.  For example, Ankita agreed to buy a Prankur car on the basis of his letter, in which the price mentioned was 50,000 Lakhs instead of 5 due to a typo. The aforementioned agreement is deemed to be cancelled due to an error in the quantity of the object. The Hynix court explains the difference between an error of law „… where the facts are known, but the legal consequences are not, or are thought to be different from what they really are… Century Importers, Inc. v.
United States, 205 F.3d 1308, 1313 (Fed. Cir. 2000), and an error of fact, „… if (1) the facts exist, but are unknown, or (2) the facts do not exist, as they are believed to [exist],“ says Hambro Auto. Corp. v. United States, 66 C.C.P.A. 113, 118, C.A.D.
1231, 603 F.2d 850, 853 (1979) („An error of fact is any error other than an error of the law.“id. to 855) Hynix, 414 F Supp. 2d. to 1325. These categories of errors also exist in the United States, but it is often necessary to identify whether the error was a „decision error,“ which is legally a mistake (in the face of two known decisions that are false) or an „ignorant error“ that is not aware of the actual state of affairs. 20. Agreement in nullig, if both parties are indeed defective An error refers to a false conviction, which is innocent, which leads one party to misunderstand the other. As a general rule, it occurs when the parties are not fully aware of the terms of the contract and understand the terms in another sense.
Therefore, there is no ad-idem consensus, that is, heads meet between the parties and therefore do not understand the same thing in the same direction. The Maxim Ignorantia Facti Excusat, which means ignorance of the fact excused. Therefore, a contract under section 20 of the Indian Contracts Act of 1872 is deemed invalid if both parties to the agreement have erred. In the case of Cooper v Phibbs (1867), the applicant took a lease for fishing directly from the defendant, unaware that he already had a lifetime interest in fishing law. Accordingly, the applicant brought an appeal to quash the lease and the defendant argued that it was an error of law. It was found that an error of general or common property was equated with an error of law and was therefore quashed. It was found that there was a unilateral error by the applicants regarding the identity of the other party cancelling the contract and that, therefore, the title of the goods was not transferred to Blenkarn and therefore could not have been transferred to Cundy, which could return the goods to Lindsay and Co.