It is valid to sign a contract with a nickname. But you need to prove that the nickname on the contract is yours. Only when the signature and seal are true can the contract be established and take effect. Inconsistency between signature and ID card does not affect the validity of the contract: in some cases, some people like to use English names when signing, but their signatures are still valid ~ but the agreement in the contract is limited to the contents clearly stated by both parties in the agreement. The so-called "Party B doodles on the back", if there is evidence that it was unilaterally added by Party B after the contract came into effect, of course, the added part has no effect on the contract. Identification can identify whether the words on the contract are formed at one time. ? Article 470 of the Civil Code of People's Republic of China (PRC) The main terms of a contract and the contents of a model contract shall be agreed upon by the parties, generally including the following terms:

(1) The name and domicile of the party concerned; (2) Subject matter; (3) quantity; (4) quality; (5) Price or remuneration;

(6) Time limit, place and method of performance; (7) Liability for breach of contract; (8) Methods for resolving disputes.

The parties may conclude a contract by referring to the model texts of various contracts.