Charged 1 order 4 times!!

My sister was charged 4 times for 1 order. We have been sending emails and following their instructions from their app, but nothing. This happened on the 2nd of October, 13 days later still no response from them. I am now scared to even use their app for rides because they might do the same to me. I feel like they are ******** us. Not impressed at all with their customers service. They can't be trusted