The most frequently asked question is "What should I do if Instagram Login is not working?".
Login is done on Instagram side. The Instagram Login Screen that you see in the Garny App is done by Instagram and not Garny.
So all problems that you may have with Login you need to solve in Instagram. We don't control Instagram Login process.
These are the steps that should help you to solve the Login problem:
Check carefully that Username and Password you're using are correct.
To make sure it's so you can even try to Logout from Instagram App and login with the credentials you're trying to put on Login Screen in Garny App.
Try to reset the password. For this you need to follow Instagram guide of resetting the password. (You can reset the password either in the mobile or desktop Instagram).
If your Instagram account is linked to Facebook - probably you don't even have the Instagram password set. That's so because by default Instagram login via Facebook doesn't require a password.
In this case you need to reset your password in mobile or desktop Instagram.
And after that try to login in Garny App with the new created password.
If it is still not helpful and you're sure that your username/password are correct and you can login with them directly into Instagram App itself, then try the following: