I'm trying to pay my subscripton, but the system does not let me update the payment method

Welcome to the Community, @felipe3.

Let me provide you troubleshooting steps on how to fix this. You can sign out and sign in back to your account.
 
If the issue persists, I suggest using a private browser. Private browser mode prevents cookies from making QuickBooks store unnecessary text files.
 
Open a supported browser and here's the hotkey:
Safari: Press Command + Shift + N
Firefox: Press Ctrl + Shift + P
Microsoft Edge: Press Ctrl + Shift + P
Chrome: Ctrl + Shift + N
 
If this fixes anything, clear your browser's cache. It helps rebuild the cache that can help download fresh copies of data. It even boosts the browser's performance.
 
Otherwise, use another supported browser.
 

If the issue continues, I recommend contacting our Phone Support Team. The tools they use there are advanced, and they can help you check your account.

Here's how:

1. Go to Help on the upper right.
2. Click Contact Us.
3. Enter your query and hit Let's talk.
4. Choose to Get a callback.
   

Our supports are available every 6:00 am-6:00 pm from Monday to Friday and 6:00am-3:00 pm Saturday.

Please let me know or tag me (@Jovychris_A) if you need further assistance. I'll be around to help. Have a happy weekend!