Double charged

I was charged twice for a ride I disputed the charge same day of the incident i was told about authorisation hold and to wait 7-10 business days for reversal . I waited still nothing, now when e disputing again they telling me they will investigate maybe a family member might have used my card, what bull is that.. i was charged just after requesting the ride and immediately driver ended ride was charged the exact amount.You failed to investigate on the same day of the dispute and said its a hold now that days have passed you want to investigate and i need to wait more days, where was the due diligence upon the initial query.