Smoking on a private balcony is generally legal but if the smoke drifts into other lots it can be a 'nuisance' breach of the by-laws. Many schemes have passed smoke-drift by-laws making it actionable when smoke affects neighbours.
Document the issue (dates, times, what unit, how much smoke) and report it to the strata manager. If a smoke-drift by-law is in place, the owners corporation can issue a notice to comply. If not, you can move a motion at the next AGM to introduce one — these by-laws are now common.
Compare written fee proposals from strata managers covering your building — free for owners corporations, no obligation.