Sorry to hear about the negative impact of that advice. Date-based automations in particular can be complex and advice can be good in one specific situation and bad in another depending on a number of variables.
Using a “Wait until” condition makes sense if all contacts are entering your automation at once. That way everyone moves through when the date hits, as a group. What appears to have happened here is that some contacts entered after the “Wait until” date and got stuck there because the condition was no longer true.
When contacts are entering at different times, it makes more sense to use Goal conditions. This way, any contact will jump forward after the date condition is met, regardless of whether they entered before or after the date condition.
To edit this automation, I’d add the Goal underneath the Wait condition you currently have. Then I’d delete the wait.
I’d recommend that you book another one-on-one though so that someone can take a look at this automation in depth and hear what you want it to do in detail. I know there may have been a misunderstanding last time but that’s very rare and I think you’d benefit from someone taking the time to examine this automation.