Feed Error

I have an issue with my RSS feed, not through feed burner (though have tried that since)

I have uninstalled & reinstalled all plugins/changed theme but nothing.

My site is:

https://mummyvswork.co.uk

I have done this:

https://feedvalidator.org/check.cgi?url=http%3a%2f%2fmummyvswork.co.uk%2ffeed%2f

Not sure if its linked but i also get a done with errors notice on the page when you open it.

Although i set the site up i’m not a massive technology wizard!

Thanks ??