I just saw someone asking about this in-game and found your post from a search. I’m not having this issue myself, but you can always pull up your current and older expansion buttons with these helpful commands.
Dragonflight
/run DragonridingPanelSkillsButtonMixin:OnClick()Shadowlands
/run ShowGarrisonLandingPage(LE_GARRISON_TYPE_9_0)BFA
/run ShowGarrisonLandingPage(9)Legion
/run ShowGarrisonLandingPage(3)WoD
/run ShowGarrisonLandingPage(2)