If multiple browsers fail, it should not be a browser problem. You can open IE and press F 12 to switch to other browser modes to confirm this problem. I think it should still be the problem of the Bank of China.
There is a tool in IE option, then Internet option, safe and trusted site, click on the site next to it, add a site, then check the restricted site, click on the site next to it, and delete the website about BOC. If you need a genuine copy, go to the website of China Banking Association to buy it, where there will be an announcement. If you don't need a genuine copy, you can buy a copy directly from Taobao, which is abundant, cheap and free of postage ... In addition, your local industry association also has this business. If you work in a bank, your company's internal system should have this announcement. If you are not an employee, buy it on the website of the association.