First, could you please tell us if you are encountering a specific error message when trying to reconnect your BMO account? Knowing the exact error code or message will help us pinpoint the issue quickly and give you the most direct solution.
Here are a few common reasons why bank accounts sometimes stop connecting to QuickBooks:
Your bank (BMO) might be performing system maintenance. We can log in to the BMO website to check for any messages, prompts, or scheduled maintenance announcements that need your attention.
Your bank credentials. Please ensure that the login credentials you are using to connect the BMO account in QuickBooks are exactly the same as the credentials you use when you sign in directly to the BMO website.
Internet connection problems. An unstable or slow internet connection can prevent bank account to reconnect or downloading transactions. We can try visiting other websites or applications that require internet access. Is those site are slow or not loading properly, then your internet connection may be the problem.