Please confirm that either of the following is setup.
1. Check to see whether your Twitter account is registered on the iPhone from the following:
Settings —> Scroll down to Twitter
If not, please tap on Add Account and enter your Twitter ID and password.
nana also needs to be allowed to use your Twitter account.
On the same screen, you will see a list of apps that uses your Twitter account.
Please make sure that nana is ON.
2. Start the Twitter app or access Twitter on your browser and login.
If the setup above is completed and you still can’t login to nana, please try either
1) Deleting and re-registering the Twitter account on your iPhone, or
2) Logging out and re-logging into your Twitter app.
When you're loging in with Twitter, you need to allow nana to use your Twitter account.
Make sure that you are logged in to the correct Twitter account on the app integration page, and are allowing nana to use your Twitter account.