Contacts not updating on iPhone or laptop

I have discovered that when I add contact information on my iPhone or MacBook Pro, they are not updated via iCloud anymore. It used to and was a handy function. I have checking settings on both my phone and laptop and everything is 'on'. So what's the problem?

I then accessed my Contacts on the iCloud web page. And I got this message.

"Contacts has stopped responding. An error has prevented this application from working properly."

Any thoughts anyone? Does some software need to be reinstalled, or updated?

Many thanks for any help

M

Phone os= 14.7.1

Mac= (Mojave) 10.14.6