I have one particular e-mail account in my organisation that my email client keeps throwing an authentication error for. 

I can initially authenticate fine, but after ten minutes or so the authentication fails and the mail client asks to re-authenticate. Once I do that everything is fine for another ten minutes, then it fails again. I have 2FA turned on and I have used an app-specific password.

I have other Zoho accounts set up in this client with no problems, it's just this one account that has the problem.

I've tried removing and re-adding the account.

Are there any settings on my zoho account side that might cause this behaviour?