Constant connectivity issues

We are have been having constant connectivity issues with both Ethernet and Wi-Fi.  For a busy bar / music venue that relies on stable internet connectivity to run POS system and payment processing (across 4 floors), back office server, as well as soundboard equipment for live performances, this is unacceptable.  Our POS system can temporarily process cards in offline mode but that is meant to be a stop gap for a temporary connectivity glitch only! Tips can’t be entered, payments cat be fully processed and end of day can’t be run. 
How can I reach a human being directly so these issues can be resolved and I can run my business efficiently???
Having to manually reset the modem multiple times in a night and pray for it to work is ridiculous. Having to go through the robot menu every time you call support is beyond frustrating, especially when you have to call back due to being hung up on or never receiving the call back from supervisors that you requested and were promised. 

Being asked to manually reset the modem EVERY time you call back is  beyond frustrating.
Asking employees and/ or musicians to use their cell phone personal hotspots to run sound equipment is embarrassing ( and risky)

Service tickets closed because support hung up on me???
AND, it’s not just the internet…. Our phones are constantly going out of service as well!!!

Basically, we are paying Comcast Business rates as well as losing thousands in sales due to our services going in and out. My business IS customer service. What you provide in the way of support to you business customers is insulting. 
It would never even cross my mind to require my customers to jump through so many hoops to get a resolution to an issue.

Why should we have to post on a forum in order to get a response to problems with your service that directly impact our businesses?