MacBook pro not updating
I can't update to Big Sur from the App Store or from the System Preferences->Software update.
I have tried more than 15 times in the past 2 weeks. I downloads upto 5M/12.xG and then fails.
I was able to update to Catalina 10.15.7 from https://support.apple.com/downloads/macos
I have more than 190G available. My wifi is fine since I'm able to play videos, movies and download stuff on my MacBook Pro.
I also can't update any of my iPhones: iPhoneSE2 iPhone6s to iOS14. I have enough space on the devices.
I have Xfinity 100 to 150Mb/s downloads speeds.
How do I debug this ?
a) I can try a Ethernet cable to MacBook.
b) What else ?
MacBook Pro 15″, macOS 10.15