I want to ensure you'll get the best help with concern, catherine-tobin.
Can you share with me if what Transactions are you referring to? This way, I'll be able to verify and check for any open investigation.
In the meantime, you need to try to connect your account using a private browser to help us determine if this is a browser-related issue. You can rule this out by using an incognito window:
Google Chrome, press CTRL+ Shift + N
Mozilla Firefox: press CTRL+ Shift + P
Internet Explorer: Press CTRL+ Shift + P
Safari: press Command + Shift + N
Log in to your QuickBooks Online account again. When you're able to do so, go back to the regular browser and clear the cache.