I have a URL with an error, but no page

I've just had a website audit, and I have two instances (so far) where there is an error on a page that doesn't exist.

For example, the error is on URL - https://www.cu-solutions.co.uk/what-we-do

I don't have any pages that are called "what we do"

Same, I have one on https://www.cu-solutions.co.uk/cart and I don't have page called "cart"

3 minutes ago, bonniergcuk said:

https://www.cu-solutions.co.uk/what-we-do

This is your Homepage, the URL for it is /what-we-do even if the page title is not What We Do. Go into the page settings for the page that is set as your homepage.

4 minutes ago, bonniergcuk said:

Same, I have one on https://www.cu-solutions.co.uk/cart and I don't have page called "cart"

/cart is a standard page on every Squarespace website.

What is the "error on the page"?

How strange. Attached is the screengrab from the settings of my homepage. 

I have a broken link 4XX on the "what we do URL" and a missing H1 on the "cart" url

That's really odd, both /what-we-do and /home seem to be the same page, and I don't know how or why that is.

The only link that I can't see working is the tel link in the footer, needs the country code.

I wouldn't worry about missing an H1 in the cart, it's not an indexable page by Google anyway.