Unacceptable timeframe to have a reverse DNS record changed

I have tried since yesterday around 11AM CST to have the reverse DNS records changed because we changed our domain name.  I had to call again this morning and ended up talking to two support representatives and the last one was finally able to get someone to make the changes.  However, they did not follow my instructions and now all my IP address resolves to just to the domain name itself.  They removed the hostnames.  So no more mail.*, www.*, etc...

I immediately called back and now I am back in the queue.  I can't even speak to a supervisor due to the pandemic.  I am very, very, frustrated and disappointed in the fact that 1) it literally takes less than 1 minute to change 5 reverse DNS records 2) even if someone eventually gets around to fixing the mistakes, it can take up to another 48-72 hours for the changes to propogate through the Internet.

My business relies on being able to send e-mails.  Without reverse DNS working right, other email servers on the Internet will likely reject, discard or report my domain as SPAM because it's no longer in compliance. I understand that we are in a pandemic, but as a business, I need to be able to rely on my business partners (Comcast, in this case) to be able to handle simple things like this within an hour or two at the most.

I am told that I can't talk to anyone for support. They can only create tickets.  This really is not acceptable.  I've been a business customer for almost 20 years and never had any problems.  I understand if this is a request to have someone physically come out and do work, but this is just modifying DNS records.

Please resolve this ASAP and put in a better process to serve your business customers.