As far as I know, all we know at the moment is that Monzo shouldn’t need to do a credit check on you, in order for you to open a current account which isn’t what you’re asking about obviously.
Just to keep everything linked together, your question was also asked here, a few days ago but we’ve not heard back from Monzo yet -
That seems pretty harsh, I’m guessing you signed up for an account with an incentive to switch of some kind then? Out of interest, which bank & account do you have?