Unable to edit bib record

[symac]

Hello,
I believe there has been some change on E-L's side or something wrong in the example.

When I try to use the example in the README file :

$bib = $alma->bibs->get('990114012304702204');

foreach ($bib->record->getSubjects() as $subject) {
    if ($subject->vocabulary == 'noubomn' && (string) $subject == 'Boating with dogs') {
        $subject->delete();
    }
}

$bib->record->appendField(new File_MARC_Data_Field('650', [
    new File_MARC_Subfield('a', 'Boating with cats'),
    new File_MARC_Subfield('2', 'noubomn'),
], null, '0'));

$bib->save();

The script seems to work fine, does not return any error (I have updated it to use a MMS id from my library). But if I look at the record in Alma, even if the modify date of the record has been updated to "now", the marc record does not contain my newly created 650 field.

Am I missing something or is this a known issue ? I am using an API Key where get/set are allowed on the bib section of the API and am using the 0.9.3 version of the library.