I am trying to upload bank transactions to qbo using CSV file. But in step 2 dropdown windows don't open. I tried everything, different browsers, Mac, windows computers

Welcome to the Community space, alonita95.
 

I recognize the importance of uploading your bank transaction in QuickBooks Online. I'm here to help you fix this matter.

But before we proceed, may I ask for a screenshot of what kind of error you get? This is for me to give an accurate solution to your concern.

Since you're unable to open the step 2 drop-down on your end, we can open your account in incognito mode to see if this has something to do with your browser. 

Here's how to access incognito mode in some of the most commonly used web browsers:

•  Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P
• Safari: Command + Option + P

If you're able to see the merging option by browsing privately, it's safe to say that it's being caused by the browser. It can be fixed by clearing your cache and cookies.

Keep me updated in the comments if you have further questions about uploading your transaction in QuickBooks Online. I'm just a reply away. Keep safe and have a good one.

@alonita95 

You can use the trial version of csv2qbo converter tool to isolate the problem.

https://www.moneythumb.com/?ref=110