The default advice for this situation is: "clear your cache." And to do that depends on your operating system/browser. I am on a cell phone, and the procedure is mercifully straightforward.

Here is what my search engine gave me:

"Why Clear DNS Cache?

Outdated Information:

Your DNS cache stores website addresses (IP addresses) you've visited. If a website's IP address changes, your browser might still use the old cached information, leading to errors. Clearing the cache ensures your browser fetches the correct IP address. 

Security:

Clearing the cache can remove potentially harmful or outdated entries that could redirect you to malicious websites. 

Troubleshooting:

Clearing the DNS cache is a common troubleshooting step for various network issues, including "DNS not found" errors."


"To clear your DNS cache and potentially resolve "DNS address not found" errors, you can follow these steps depending on your operating system: 

Windows:

1. Open Command Prompt as administrator:

Search for "cmd" in the Start menu, right-click on "Command Prompt," and select "Run as administrator."

2. Flush the DNS cache:

Type ipconfig /flushdns and press Enter. This command clears the DNS cache, forcing your computer to fetch fresh DNS information for websites. 

macOS:

Open Terminal: Search for "Terminal" in Spotlight search.Flush the DNS cache: Type sudo killall -HUP mDNSResponder and press Enter. This command restarts the mDNSResponder process, which manages DNS caching on macOS. 

Linux:

Open Terminal: Search for "Terminal" in your application menu.Flush the DNS cache: Type sudo service network-manager restart and press Enter. This command restarts the network manager, which manages DNS caching on Linux. 

Chromebook:

Go to Settings: Open the Chromebook Settings menu.Search for "DNS": Search for "DNS" in the settings.Clear DNS cache: Select "Clear DNS cache" to clear the DNS cache. 

Other Troubleshooting Steps:

Restart your router:

A simple restart can resolve temporary network issues that may be causing DNS errors. 

Restart your computer:

Restarting your computer can also resolve temporary software or network glitches that may be causing DNS errors. 

Scan for malware:

Malware can interfere with DNS resolution. Scan your computer for malware and remove any detected threats. 

Reset network settings:

On Android or iOS, you can reset network settings to clear DNS and other network-related configurations."

HTH