Gym Company Is A ****

when i joined the gym they told me that i can cancel the contract anytime, few month later they told me i cant cancel but transfer so i transferred it to one of your consultant who made me pay , i asked if am owing anything , they said no,last week i was called and told that i owe 900 and should pay it or else i'll get blacklisted , this company is a ****, clear my ITC or else we'll meet in court