DNS Settings not updating even with reduced TTL

I'm setting up a new domain www.verifiedsupply.com using Google Cloud DNS. See below:

However, I don't think the DNS settings are updated properly. I have reduced the TTL for the settings to take effect immediately but it doesn't get updated and I am still forwarded to the wrong address.

Is there a minimum time required for changes to take effect? What can I do to make the update work immediately?