Legal analysis: If there is other evidence, you can directly confirm the labor relationship. If the other party doesn't sign a labor contract, I can claim to double my salary without signing a labor contract. If negotiation fails, actively collect evidence and apply for labor arbitration for compensation. When workers encounter such problems, they should safeguard their legitimate rights and interests through legal channels.

Legal basis: People's Republic of China (PRC) Labor Contract Law.

Article 7 An employing unit shall establish labor relations with laborers from the date of employment. The employing unit shall establish a roster of employees for future reference.

Article 10 To establish labor relations, a written labor contract shall be concluded. If a labor relationship has been established and a written labor contract has not been concluded at the same time, a written labor contract shall be concluded within one month from the date of employment. If the employer and the employee conclude a labor contract before employment, the labor relationship shall be established from the date of employment.

Article 82 If an employer fails to conclude a written labor contract with the employee for more than one month but less than one year from the date of employment, it shall pay the employee twice the monthly salary. Where an employing unit violates the provisions of this Law and fails to conclude an open-ended labor contract with the laborer, it shall pay the laborer twice the salary every month from the date when the open-ended labor contract should be concluded.