If the Ownership & Title of the Society Ground (property) is in the name of the Society, THEN ONLY only the Society can given its Ground on Rent, that too after passing resolution by 2/3 majority in the General Body meeting. This resolution should be approved by the Registrar of Socities.
However if the Ownership & Title of the Society Ground is NOT in the name of the Society (i.e. if the property conveyance is not done) THEN the Society CANNOT give the Ground on rent, even if it is passed in the General Body meeting (AGM's).
You can complain in the District Consumer Forum about the Deficiency in Service (by the Society) for malfunction of the Lift due to Commercial usage (taking rental/fee for renting ground). Take some photograph of the functions. Also lodge a NC with the local police station, for evidence purposes.
You can also complain to the Registrar of Socities to stop this Anti-Society nuisance, terming it as "damage to the society property", by filing a petition.
You can also complain to the Muncipal Corporation for the same, since renting private residential property for commercial activities, needs special permission from the Muncipality and the Police dept.
BY THE WAY, how does the lift get non-functional if the Society Ground is used.
Keep Smiling ... HemantAgarwal