Import the LDIF files into the database error

Hello,

When I trying to use the following command to Import the LDIF files into the database, I will get a error message:

ldapadd -a -W -x -D "cn=Manager, dc=exapmle, dc=com" -f example.com.ldif -h 192.168.0.200
Enter LDAP Password:
ldap_bind: Invalid credentials

If I type secret for password, I will get a error as above

or

If I just press enter for password, I will get a error as below:

ldapadd -a -W -x -D "cn=Manager, dc=exapmle, dc=com" -f example.com.ldif -h 192.168.0.200
Enter LDAP Password:
adding new entry "dc=example,dc=com"
ldap_add: Insufficient access

ldif_record() = 50

##################
example.com.ldif
##################
dn: dc=example,dc=com
dc: example
description: Root LDAP entry for example.com
objectClass: dcObject
objectClass: organizationalUnit
ou: rootobject

dn: ou=People, dc=example,dc=com
ou: People
description: All people in organisation
objectClass: organizationalUnit
###################

###################
slapd.conf
###################
database ldbm
suffix "dc=example,dc=com"
rootdn "cn=Manager,dc=example,dc=com"
rootpw secret
directory /var/lib/ldap/example.com
####################

Can anyone help? Many thanks.
Ditto