can anyone please guide me for changing objectclass

Current objectclass
objectClasses: ( 2.5.6.6 NAME 'person' DESC 'RFC2256: a person' SUP top STRUCTURAL MUST ( sn $ cn ) MAY ( userPassword $ telephoneNumber $ seeAlso $ description ) )

Wanted like this
objectClasses: ( 2.5.6.6 NAME 'person' DESC 'RFC2256: a person' SUP top STRUCTURAL MUST cn MAY ( sn $ userPassword $ telephoneNumber $ seeAlso $ description ) )

tried to change by using below command
$ldapmodify -d -1 -D "cn=admin,dc=example,dc=com" -w secret -f modify.ldif

$cat modify.ldif
dn: cn=schema
changetype: modify
add: objectclasses
objectClasses: ( 2.5.6.6 NAME 'person' DESC 'RFC2256: a person' SUP top AUXILIARY MUST cn MAY ( sn $ userPassword $ telephoneNumber $ seeAlso $ description ))



getting error
ldap_modify: Invalid syntax (21)
additional info: objectclasses: value #0 invalid per syntax

Thanks in advance