There are a few possible reasons for a non-working trade button. The most common ones are:
1) The market is closed
2) You haven’t filled in all the details for a trade
However, if in your case both are not applicable, it might be the case that something more technical is going wrong:
3) The app is stuck
4) There is a miscommunication with our server
If there is a more technical issue, please close the app completely and complete a full restart of the application.
If you have any further questions in regards to this, please feel free to contact us via email at BUX Support.