Anchor or button nested inside other anchor or button
Interactive control elements MUST NOT have focusable descendants.
Invalid code - such as incorrectly nested elements - doesn't always cause accessibility problems, but it can, especially if there are errors in the parts of the markup that screen readers rely on to communicate the semantics of the web page to users. Focusable elements with an interactive control ancestor (any element that accepts user input such as button or anchor elements) are not announced by screen readers and create an empty tab stop.
Fix this issue by ensuring that button and link elements do not contain other button or link elements or any other interactive elements.