Thanks for posting and for being a step ahead of us.
This is not the experience that we wanted you to have, let me help you out. A few things: which chromecast device? Is this for a new Chromecast setup? You can do a full reset then set it up as a new device. Check the steps below.
Factory reset Chromecast (2nd gen), Chromecast (3rd gen), or Chromecast Ultra:
Factory reset Chromecast with Google TV:
Set up Chromecast or Chromecast Ultra
Below are the helpful articles that you can also check.
Let me know how it goes.