Did any Hogwarts Professor ever forget their student's name?

Question

Inspired by this question, Hogwarts Professors seem to be teaching a lot of students. They (core-subject teachers) teach at least 280-300 students. They'll have to remember that many names, and it doesn't seem like any Professor forgets anybody's name.

During students' first lesson with them, a name-list is used for the teacher to identify the student.

Professor Flitwick, the Charms teacher, was a tiny little wizard who had to stand on a pile of books to see over his desk. At the start of their first class he took the roll call, and when he reached Harry's name he gave an excited squeak and toppled out of sight.

_{Harry Potter - The Philosopher's Stone: Chapter 8 - The Potions Master}

An exception would be Umbridge, who doesn't take attendance during her first lesson:

Professor Umbridge raised her eyebrows.

'And your name is?'

'Hermione Granger,' said Hermione.

[...]

'We're not going to use magic?' Ron exclaimed loudly.

'Students raise their hands when they wish to speak in my class, Mr—?'

_{Harry Potter - Order of the Phoenix: Chapter 12 - Professor Umbridge}

Of course, there are students who are famous -Harry, and notorious -Draco, who teachers would have no trouble remembering. But what of those that are not? Hogwarts Professors would have a lot of names to remember.

So, were there any instances where a Hogwarts Professor forgot/wrongly say a student's name?

Answer 1

Yes, there were a few instances stated in the books.

The first instance is in Chamber of Secrets, where the class questioned Binns about the Chamber. Binns clearly gets all 3 of his students' names wrong.

At first, he is told Hermione's surname:

'Miss— er—?'

'Granger, Professor.'

[...]

'My subject is History of Magic,' he said in his dry, wheezy voice. 'I deal with facts, Miss Granger, not myths and legends.'

_{Harry Potter - Chamber of Secrets: Chapter 9 - The Writing on the Wall}

Then, short-term memory loss syndrome kicks in:

He stuttered to a halt. Hermione's hand was waving in the air again.

'Miss Grant?'

[...]

'But, sir,' said Seamus Finnigan, 'if the Chamber can only be opened by Slytherin's true heir, no one else would be able to find it, would they?'

'Nonsense O'Flaherty,' said Professor Binns in an aggravated tome.

'But, Professor,' piped up Parvati Patil, 'you'd probably have to use Dark Magic to open it—'

'Just because a wizard doesn't use Dark Magic, doesn't mean he can't, Miss Pennyfeather,' snapped Professor Binns.

_{Harry Potter - Chamber of Secrets: Chapter 9 - The Writing on the Wall}

The second instance is in Order of the Phoenix, in Binns' class again:

'Not at all well,' said Harry firmly, getting to his feet with Hedwig concealed behind his back. 'I think I need to go to the hospital wing.'

'Yes,' said Professor Binns, clearly very much wrong-footed. 'Yes ... yes, hospital wing ... well, off you go, Perkins ...'

_{Harry Potter - Order of the Phoenix: Chapter 17 - Educational Decree Number Twenty-Four}

He even forgets the famous Harry Potter's (sur)name.

Another instance would be Slughorn's case:

'There you are, then,' said Slughorn, handing Harry and Ron a glass of mead each, before raising his own, 'Well, a very happy birthday, Ralph—'

_{Harry Potter - The Half-blood Prince: Chapter 18 - Birthday Suprises}

So, in the first two instances it is the teacher: Professor Binns, who forgets his students' names. Probably due to the fact that he was pretty old. The other is in the more notorious case of Slughorn, who doesn't bother remembering the names of 'not-talented' students.