I need help with my ollies?

I know how to ollie and a bunch of other stuff but for a long time when i ollie my board shifts to the right and since it moves i have to which makes it look like im doing a halfway Fs ollie.....personal i think its my board ive had it for over 2 years now and i think the tail is messing me up ive tryed switchin my feet position in different ways but it always pops to the right what do you guys think?