Why did my bank account disconnect from QuickBooks?

https://quickbookhelpdesk.com/blog/reconnect-bank-account-quickbooks/

A bank account may disconnect because of password changes, bank security updates, expired authorization, browser issues, internet connection problems, or temporary maintenance by the financial institution. A disconnected bank account in QuickBooks can interrupt your bookkeeping process, but it is usually a temporary issue that can be resolved without much difficulty. Connection interruptions are commonly caused by updated banking credentials, security verification requirements, browser issues, or temporary communication problems.