If you're using the iPF app, then the solution is to close the app completely. Double tap the Home button to open the multi-task bar, then press and hold any icon in the multi-task bar until they all start to jiggle, then press the top left hand corner of the iPF app icon to completely close it. Then press the Home button again to close the multi task bar and see if the problem persists.
If you were seeing this problem when using the web site version, then do the same procedure, but close Safari instead.
Tim