In NeoBT mobile banking: 

Before logging into the app, you can change the language by going to "Settings", then "Change language". And after logging in, by going to "Your profile" from the main page right-up and "Change language".

In NeoBT internet banking: 

You can change the language from the login page on the bottom right of the page. Once logged in, you can do the same by clicking on your name at the top right and accessing the list immediately below your name. 

See yaa! 👋