How to stop Instagram account from auto- following random accounts?

The fix is simple: You need to head to your Web profile and check out what applications you’ve given access to. Anything suspicious needs to go. Then change your password. Of course, also stop following the guilty parties who you’ve suddenly found looped into your Instagram feed.
Of course the fact that you can easily dismiss this batch of random, like-hungry Instagrammers isn’t really the issue. It’s the fact that the spamming problem is escalating for Instagram, and it’s happening fast.
You can also follow the below steps as well.
1 Go to Instagram website from your computer (cannot be done from the app)
2 Go to your profile and click Edit Profile.
3 Select Authorized Applications from the right-hand side menu.
4 Click Revoke Access on the ones you don't want to keep.

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