problem with changing payment card for subscribtion

I can definitely help you update your payment details, Dusan. 

There are a few things that we can consider when updating your bank account information. I'd like to ask  if you got an error when tying to update so I can give you further steps on how to resolve it. If you're subscribed through Google Play or iTunes you'll need to modify your billing information with them. We can also check your billing address if it matches the address that's in your bank. 

We can use a private browser to update your billing information. You can use these keyboard shortcuts based on the browser you're using.

• Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Internet Explorer: Ctrl + Shift + P
• Safari: Command + Shift + N

Once you have opened the private window, let's log in to your QBSE account and update your billing and subscription details: 

1. Go to the Gear icon at the upper-right and select Billing info. 
2. Click the pencil icon in the Payment Information section. 
3. Update the card information.
4. Select the checkbox off screen to acknowledge and confirm your subscription.
5. If you update your billing address, fill out the current and correct address in the next section.
6. Select Update and Close (X) when done.

Keep me posted on how this works. I'll keep an eye on it!