There could be several reasons why your friend's Instagram account suddenly shows 0 posts and 0 followers, despite having around 100 posts and 300 followers just a day before. Some possibilities include:
Account Deletion: Your friend might have decided to delete their Instagram account altogether. When an account is deleted, all the posts and followers associated with it are removed.
Temporary Suspension: Instagram may have temporarily suspended or disabled the account due to a violation of their community guidelines or terms of service. This could be the result of inappropriate content, spamming, or other violations.
Hacked or Compromised Account: The account could have been hacked or compromised, and the hacker may have deleted the posts and unfollowed all the followers.
Technical Glitch: It's possible that there was a technical issue with Instagram that caused the posts and followers to temporarily disappear. However, such glitches are usually resolved quickly by Instagram's technical team.
Privacy Settings: Your friend might have changed their privacy settings to make their account private, which would hide their posts and followers from public view.
Mistaken Action: Your friend might have accidentally deleted the posts or unfollowed all the followers, and they are unaware of it.
Bot or Automated Action: In some cases, bots or automated actions can cause unexpected changes to an account, such as mass deletion of posts and followers.
If your friend did not intentionally delete their account and is unsure of what happened, they should reach out to Instagram's support team for assistance. They can try logging in again and check the account settings to see if anything seems amiss. It's also a good idea for them to review their recent activity and look for any suspicious logins or actions that they didn't initiate.