Unsure of why you were charged twice? 

It's possible that while riding, you went beyond the time that's included in your pass type. We have these time limits in order to keep the bikes in circulation and available for other riders. If your ride exceeds the covered time limit of your ride pass type, non-members will be charged $0.30/minute for every additional minute. Members will be charged $0.20/minute for every additional minute. All per-minute ride prices are rounded up to the nearest minute.

Note: If you are charged for any extra time, your card on file will be charged. The fee for a lost or stolen bike is $1,200 (+ tax).