Welcome to the Community, Polaris Architecture.

Since you're unable to connect to your bank, I'd initially recommend signing in to the account you have with them and confirming if they use any multi-factor authentication. This can sometimes cause issues with third party connections. Sometimes, when they do use these types of authentication codes, you'll be able to turn the option off in your account settings. If you decide to turn such a setting off, you'll want to check their website or support for steps on how to do so.

While you're signed in on the bank's website, also check for any messages or notifications. These can also cause issues if left unacknowledged. Be sure to acknowledge any messages or notifications while signed in to your account.

Since you've updated the account's password, I'd recommend making sure that you've updated it in QuickBooks.

Here's how:
 

1. In your left navigation bar, go to Transaction, Bank transactions.
2. Click the tile for your bank account.
3. Hit its Pencil (Edit) icon.
4. Select Edit sign-in info.
5. Make any necessary changes.
6. Initiate another manual download by selecting Update.

Since you've already cleared cached data/Intuit-specific cookies and tried connecting from a different computer, I'd recommend confirming you're using a supported browser.

Here's our list of supported browsers:

• Google Chrome - version 78 or newer
• Mozilla Firefox - version 76 or newer
• Microsoft Edge - version 79 or newer
• Opera - version 68 or newer
• Samsung - version 10 or newer
• Safari - version 12 or newer

QuickBooks supports the current and two previous versions of browsers. If you find that you're using an unsupported version, make sure to update it to its latest release. Steps for doing so can be found on the particular company's website.

In the event you've found no problems that could be causing this with your browser, you'll want to check the operating system and internet speed you're working with.

Here's our recommended operating systems and internet speeds:

• Windows PC - Windows 10, Intel Core i3 or a comparable processor (2013 or newer) with at least 2 GB of RAM, or Windows 10, Intel Core i5 or comparable processor with at least 4 GB of RAM.
• Mac - OS X El Capitan 10.11, OS X High Sierra 10.13, or newer.
• Linux - QuickBooks works with Linux, but you'll want to make sure you're using a supported browser and our recommended internet speeds.
• Internet connection - 1.5 Mbps to 3 Mbps or higher.

If you meet each of our system requirements, but are still unable to connect with your bank, I'd recommend using a different supported device and/or internet connection. If it continues happening on other supported devices and internet connections, you'll want to get in touch with our Customer Care team. They'll be able to pull up the account in a secure environment, conduct further research, and create an investigation ticket if necessary.

I've also included a detailed resource about system requirements for QuickBooks which may come in handy moving forward: System requirements

Please don't hesitate to send a reply if there's any questions. Have a wonderful Tuesday!