1. Reschedule: negotiate with the contractor to find a suitable time to complete the signing process.

2. Use electronic signature: Transportation companies use electronic document management system, and can consider using electronic signature to complete the signing process.

3. Extend the contract period: communicate with the department or management to extend the contract period.

4. Provide training and guidance: The shortage of signers is due to insufficient understanding or familiarity with the training process, so additional training and guidance can be provided.