I can not use my paybill in quickbook online , while I want to do paybill it not shows the balance of my suppliers.

I've checked our records for open investigations similar to your concern, Ghawsi-safiullah. I've seen none.

Let's ensure that there are no credits applied to the bill. It's one of the reasons why you're unable to view the supplier's transaction or balance when paying. You'll have to open the bill and check if the credit is applied.
 

If there are no credits and the bill is still open, this unexpected behavior can be caused by too much cache. Let me help you fix it. We'll have to perform the basic troubleshooting. Let's start by opening the program using an incognito window. It's the best place to identify browser hiccups. These are the shortcut keys:

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

If you're able to see the supplier's balance, you can go back to the main browser, then clear the cache to refresh it. We advise our users to delete them frequently to avoid web issues. 

Also, you can use a different browser to help us narrow the cause of this behavior.

Let me include the article on how to track bills and record the payments as a future reference: Enter bills and record bill payments in QuickBooks Online.

You can get back to this thread if you need more help. We're just one comment away. Keep safe!