It sounds like it is nothing to do with the local council. If your estate hasn't yet been 'taken in charge', then forget about the council. If it has been 'taken in charge', then forget about the residents committee, and chase the council.
Actually, forget about the 'residents committee'. You need to contact the management company, who have probably appointed a management agent. If problems are dragging out, consider going along to the next management company agm and helping to sort them out.