Welcome to our forum and thanks for contacting us with your issue!
I've tried to reproduce your issue in a varivide
chart, but to no avail, since the yAxis is displayed even when zooming into one point. Could you please provide your config, so that I can investigate it further? You can start by editing below demo: https://jsfiddle.net/BlackLabel/dgLmbuzj/
I'm waiting for your reply.