Parsing error when submitting sitemap to Google Console

Hi,

I’m trying to help a friend who is having issues submitting their sitemap to Google Console.

The sitemap was create using the Yoast Plugin, the url is: https://www.mythreeandme.co.uk/sitemap_index.xml

In all it states there are 5 errors and gives the description:
We were unable to read your Sitemap. It may contain an entry we are unable to recognize. Please validate your Sitemap before resubmitting.

I have tried deactivating and reactivating plugins to check if any are an issue but this doesn’t fix the issue.

I have also looked at function.php and the theme files to see if there were any white spaces and I couldn’t see any.

Please can anyone help with this issue?

Thanks.

The page I need help with: [log in to see the link]