The peculiarity of working on the Internet is that you refer to the addresses of web pages, which, in fact, are links. It so happens that links on your or a third-party site become inoperative, disappear. However, there are ways to restore them.
When working on social networks such as VKontakte, keep in mind that links can be marked as spam if you send letters of the same content with a link or just a link. Before sending this kind of message, it is better to start a small dialogue in which you need to explain that you want to attract the attention of a friend to this page. If the message was posted to the wall, after being marked as spam, you can resend it by telling a friend that it is not spam. If you yourself accidentally deleted a message from your wall, an information window will appear where you will be prompted to restore the message. You can delete and restore a message in this way until you refresh the page. After that, recovery will not be available. A similar situation occurs with comments on photos, videos and on the walls of groups.
If you received an email with a link to your email and was marked as suspicious, it will be placed in your Spam folder. On different resources, the message is stored in this directory for different time, after which it is permanently deleted. However, up to this point, you can restore the desired text message by marking it and clicking the "Restore" button. The message will be sent to your Inbox.
If you have used standard HTML tags, HTML editors, or a website builder such as Yandex. People”, to insert a link or hyperlink, and it disappeared, you need to check if you saved the changes on the page and if you entered the hyperlink correctly. If the link stopped translating to the desired page after a while, check it for performance. Perhaps the site to which she leads is blocked, has ceased to exist. Then find a page with similar information and enter a new address to go.