Ritz Carlton at Laguna Niguel.. is it me or is it them?

Given that most places are still remote-work, and the restrictions currently in place, I can see how changes can take some time.

That said, the mistakes are a red flag, here.

If you're not happy, I'd move on.

Generally, I'd say walk away from poor communication, material errors, and bad customer service. However, especially in So Cal right now -- and particularly in the hospitality industry -- I'd probably give a bit more grace, if you really love the venue. As others have said, the hotel is likely operating with a minimal staff. I'd also assume they are currently unable to host any events, so the limited event staff is likely spending a lot of time on current and upcoming events that need to be cancelled/rescheduled. Typically, I'd expect a very high-level of service from the RC-brand, but these aren't typical times. If you have a clear second-choice venue in mind, you might try calling them to see if they are able to provide the service you expect -- you might find their response to be similar due to the many unknowns.

FWIW We have a relative in event management at a very high-end property in Scottsdale, AZ, and as you might guess the pandemic has been a nightmare. The entire staff was laid off for more than 6 months, and the property only recently brought back about 20% and let everyone else go.... For our relative, she's truly been left wondering if she was the "lucky one" to be kept on in an impossible situation.... Good luck!