@MariaSoledadG I am dealing with US Bank. This is a big bank in the US, so I'm not sure why it's not working. I have so many clients with this bank and every single customer is struggling with this. If you manually click update on the Banking screen or the system automatically tries to update, it automatically disconnects. They have to reconnect every single time.
I was also having this issue - I tried in both Chrome & Firefox and couldn't resolve it, but doing it in an Incognito session in Chrome did the trick and everything is working fine now. If you're still having trouble make sure you try it in an Incognito session!