Binary type has different affinity key fields

[Thomas Isaksen]

I have no idea why I am getting this exception. It occours when I try to do 
cache.put(...)

class org.apache.ignite.binary.BinaryObjectException: Binary type has different 
affinity key fields [typeName=no.toyota.gatekeeper.ignite.key.CredentialsKey, 
affKeyFieldName1=id, affKeyFieldName2=username]

CredentialsKey fields:

private long id;
@QuerySqlField(index = true)
@AffinityKeyMapped
private String username;
@QuerySqlField(index = true)
private String password;