Misleading advertising wrt refunds on Kulula bookings

My Kulula flight booked through Discovery was scheduled for mid July. Discovery's website (under Discovery Travel) and all media comms clearly states that they will give refunds for flights departing from 1 June onwards. My claim was rejected because my flight departure date was in July. When querying it I pointed out that their website and media comms clearly stated from 1 June onwards. Their response was that the qualifying period was 1 June to 30 June. When I challenged them they said I should read the terms and conditions.

Their advertising is clearly misleading in that it clearly states 1 June onwards and does not refer to it ending 30 June - they should not be allowed to get away with this.