Getting External Links with High DA

Hi Guys i have been working for my page to get external links such that I have been following high DA links to get links. But these links once approved the links which i have placed getting into 404 error and not showing. whereas the low DA sites getting indexed with proper link which i have placed. what is the way to get avoid of 404 error in high DA

404 would mean the page where link was placed was removed. Probably because cont net wasn't very good and moderators removed it.

404 = pages removed.