Meet Up review: subscription wrongly charged

I had taken a 6 month subscription
It was to auto renew on 2nd april

Promptly before a day before I tried cancelling the service, the msg I got was that there is some problem and we are not able to charge you the next subscription. So there was no option to cancel

N now I see that the subscription has been charged, absolutely unfair. I went ahead n deleted my meetup account as well... And not sure how do I reach them or get this resolved!