Soft 404 errors

[Qqkyu]

Description
App returns "soft 404" errors for missing pages. A soft 404 is a URL that returns a page telling the user that the page does not exist and also a 200 (success) status code. It returns a page with little content, namely a menu bar, and items.
Returning a success status code rather than 404 (not found) is a bad practice. A success status code tells search engines that there's a real page at that URL. As a result, the page may be listed in search results, and search engines will continue trying to crawl that non-existent URL instead of spending time crawling real pages.

https://app.moneytracker.cc/broken/url returns following page:

Steps to reproduce

1. Go to https://app.moneytracker.cc/broken/url
2. Create account and proceed if needed
3. Above site image shows up

Fix ideas

• Return a 404 (not found) or 410 (home) response (status) for the page. These status codes indicate to search engines that the page doesn't exist and the content should not be indexed
• Make these error pages useful to users by customizing them, custom 404 page should help people find the information they're looking for
• Tell visitors clearly that the page they're looking for can't be found
• Make sure the 404 page has the same look and feel (including navigation) as the rest of the app
• Consider adding a link to the site's home page

Reference
https://developers.google.com/search/docs/advanced/crawling/soft-404-errors?visit_id=637772503729817225-2301542019&rd=1