What methods are available to distinguish the DN number from the first year when submitting a new application for a CFCA Guomi (SM cryptography) certificate in the second year

When applying for a new CFCA Guomi (SM cryptography) certificate in the second year, the DN must be differentiated from that of the first year. What methods are available to achieve this?

1. Modify the content of the OU field
2. Remove the OU field