my initial thought would be that you have an axis assigned to fuel cock which is 'overiding' your button presses. You mention allied planes- have you tried spit and Hurri? I ask cos spit (and stuka have reversed control on axis

)
as you have reset controls (you did hit apply after?- not back?)this is unlikely but always worth checking
Have you also checked that you don't have a 'sticky' button on your hotas? (check in windows game controllers).
if all is good maybe try delete any fuel cock assignments then try mouse control?
good luck