Given you called AC as soon as it was declined (which may or may not be within minutes of it actually trying to charge you I guess) it’s a shame, albeit not a surprise, that AC can’t push this through in these conditions.

But we’re dealing with an airline know to fly with empty J seats when people have literally stood there offering them $3k for an upgrade. The staff are limited by the systems.

Plusgrade is likely the issue.

And btw flying once a month isn’t that much for some here