In order to eliminate DNS cache as the culprit, you’ll need to clear it. The steps for clearing your browser cache will depend on the device you're using. Different operating systems have different interfaces for accessing these settings.
Mac OS
1. On Mac: Open Finder.
2. Click Applications.
3. Scroll down to the Utilities folder and click it.
4. Open Terminal.
5. In the Terminal window, enter the following command string: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
6. Click Enter, then input your admin password.
7. Click Enter again.
Flush DNS Windows
1. Click the Start button. It’s the Windows logo in the bottom left corner.
2. Select Command Prompt.
3. To open the command prompt console, you could also simply press the Windows and R keys at the same time and enter cmd.
4. You may see a popup asking if you want to allow Command Prompt to make changes to your computer. If you do, select Yes.
5. If you are asked for an administrative login at this point, then you’ll need to contact your system administrator to proceed.
6. In the command prompt window, type ipconfig /flushdns.
7. Press Enter.
8. You should see a message confirming that the DNS Resolver Cache was successfully flushed.