No result for SSOXType=3

Hello, I have OpenLDAP v2.2.29 with a local schema. When I launch a search request with filter SSOXType=3 I get no result but it exist. Here my part of schema and ldap contenance :

Schema line : attributeType ( 1.3.6.1.4.1.11454.1.5.8 NAME 'SSOXType' SYNTAX 1.3.6.1.4.1.1466.115.121.1.27 SINGLE-VALUE X-ORIGIN 'Avencis' )

And ldap (in ldif) : version: 1 dn: SSOXName=SSOXSecrets,ou=SSOX,dc=avencis,dc=com objectClass: SSOXConfiguration SSOXComment:: U1NPWCBTZWNyZXRz SSOXCVersion: 1 SSOXName: SSOXSecrets SSOXParameter:: no communicated values SSOXParameter:: no communicated values SSOXParameter:: no communicated values SSOXParameter:: no communicated values SSOXType: 3

Thanks for your answer.

PS : Sorry if my English isn't very good, I'm French.