Well, unfortunately your impression is wrong. Only buses can stop at these restricted bus stops. There will be a sign stating this somewhere along the bus stop: -
https://maps.app.goo.gl/LRV4EV1XqvP1utgS9Looks like the little neds have been at this one, but the message is still clear.
However, this doesn't mean it's now game over, because the council management of the enforcement process may be in error at some stage. As a start, go onto their website and look at the pages for submitting representations. The statutory grounds for an appeal should all be there; are they ? As for the PCN, can you please post all pages, please so we can check it for fatal errors.