At times, unusual behavior may occur in QuickBooks Online. Stored cache files on your browser can sometimes cause this to happen. QBO utilizes cache files that temporarily save your browsing data. However, too much may lead to errors or performance issues like the one that you experienced.
To get past on this hurdle, let's access your account using a private window. Doing this stops the cache files from saving new data and makes your browser work fresh.
Here are the different keyboard shortcuts to open them:
Google Chrome: press Ctrl + Shift + N
Mozilla Firefox: press Ctrl + Shift + P
Internet Explorer: press Ctrl + Shift + P
Safari: press Command + Shift + N
From there, you may run your check module again. If you're able to access it smoothly, go back to your regular browser and clear the cache.
You can also visit these links below about fixing the loading behavior and the different tutorials in QBO for reference: