The instructions apply to the latest version of the Instagram mobile app and the desktop website.
andWindows, do these things:
Find the blocked user in Instagram.
Tap theprofileyou want to unblock.

TapUnblockand confirm that you truly want to unblock the user.
Log on to your Instagram account if you are not yet logged in.
throw in theusername of the accountor name of the person you want to unblock.

Now pick the desireduserfrom the auto-complete suggestions.
Instagram may show the user account as unavailable.
SelectUnblockand confirm that you truly want to unblock the user.

Now you’re free to follow the user you just unblocked on Instagram.
Go to yourprofilepage in Instagram.
Tap the menu button and then selectSettings.

This is also useful to unblock users who may have blocked you.
However, even though you have unblocked them, they will still have to unblock you on their end.
The user will not be notified when you unblock them.
You also cannot follow a blocked account until you have unblocked it.
To follow the user again after you have unblocked them:
Look for and open theuser’s profilein Instagram.
This works in the Instagram apps for iOS and Android just as well as it does on the web.
If you stop seeing updates from someone,find out if they unfollowed you on Instagram.
Can You Unblock Accounts That No Longer Exist?
Their names will appear on yourBlocked Accountslist with no way to interact with them.
If possible, try the Instagram app on a different platform.
FAQ
Instagram won’t notify you if you’ve been unblocked by someone.
Instead, search for the profile.
Rather, they’ll find a notice that your profile is private to anyone who doesn’t follow them.