“In the rare cases where errors are identified, the majority of cases are resolved within 24 hours.” The Home Office indicated the problem Webb encountered had since been fixed and that staff would contact her directly.

so yes, they can and do override the system.

Also the person wasn't stuck in the airport, they were denied boarding of the plane because there was an issue with their identification documentation.

It's not good, its a travesty that you even need an ID to fly between two european countries, let alone a visa, but the picture you paint is at odds with reality.