New User - Call quality is terrible.

I just setup my Ooma service and canceled my service with my Internet Provider.
I get 227 mbps download and 12 mbps upload speeds.
The quality is very muffled and sounds fuzzy. Hard to understand people.
What could be wrong.
Installation had no issues.
Also it does not seem like I can receive calls. I tried from my cell phone and it won’t ring my phone and gives me an all circuits busy message.

Update - Called support and could not solve issue. So I decided to add a second Phone number to my account. Calling that 2nd phone number from my cell phone works fine. Calling my primary number gives me a “all circuits busy” message and does not work. Call quality still very bad.

Any ideas?

Maybe you could try another phone?

Not sure what that would do as it is a Panasonic Dect 6.0 new phone system that worked fine with Comcast VOIP system.