hey there, were you perhaps playing during a helltide event?
Because im specifically losing my elixir of demon slaying buff when i switch FROM a helltide zone to a non-helltide area/zone (or to an adjacent “safe” town thats part of the helltide area).
Other than that im not losing elixir buffs when zoning throughout the world from normal to normal areas (as intended).
Elixir buffs have a timer, is it maybe possible you noticed the elixir buff missing because the buff time ran out? Elixir buffs also disappear when you logout and log back in.
i also made a threat about it myself, Possible Elixir buff bug!