I am running google home app on an iphone 14 with most up to date IOS software and google home app. Everytime I try to create a new routine or edit an existing one I get a 403 error and it says "We're sorry, but you do not have access to this page. That's all we know". I have tried googling this issue and reading multiple forums and cannot find anything useful.
That certainly hasn't been easy for you — let's see what's going on.
A few questions: are you using a private home network? When did it start happening? Also, have you tried reinstalling your Google Home app? Could you try using a different mobile phone to see if you'll get the same result?