What is instagram account suddenly private?

An Instagram account may suddenly become private if the account owner decides to change their privacy settings. This means that only approved followers can see the content on the account. If an account was previously public and then became private, it is possible that the owner may have done so to control who has access to their posts and information. There are also cases where an account may become private as a result of a security concern or a violation of Instagram's community guidelines. In such cases, Instagram may temporarily or permanently deactivate the account.