Can not ger private RSA key

[k06a]

Sometimes I got:

Error getting RSA private key: Error Domain=com.kishikawakatsumi.uickeychainstore Code=-34018 "The operation couldn’t be completed. (com.kishikawakatsumi.uickeychainstore error -34018.)"

for this code:

NSError *error = nil;
NSData *key = [UICKeyChainStore dataForKey:self.privateKeyTag error:&error];
if (key == nil) {
    NSLog(@"Error getting RSA private key: %@", error);
    return nil;
}

[gabu]

FYI #14