I am searching for a word or a couple of words to describe the following situation:
A login webpage isn't working (i.e. someone can't log in) (for example the login page of Gmail). A user is trying to login, through multiple attempts and in different ways, without success. He asks an expert for advice about this issue and that specialist comes to help him. The expert tries to login with the user's device, doing what looks like the same exact procedure, and the login works at the first try.
In this situation it looks like the "presence" of the expert was the only difference between a failed login and a successful login.
I am looking for a word to describe this situation where just the very presence of an expert seems to changes the outcome of the situation without the expert doing anything on purpose, just acting normally.
UPDATE:
Example sentence in which I would use the word I am looking for:
Let me think about it.