You can't! The only way I got a response from them was when they emailed me to rate my driver and I gave a bad review for her and Instacart. I got an email back. Otherwise, there is no Customer Service! I tried everything under the "Help" section and got nowhere!

1(888) 256-7822 was given to me by Wegmans. I've not contacted them as I was so disgusted with their service.

I don't think you can. The first call I made to them, I stayed on hold for over 2 hours before they answered. This time I stayed on hold over 4 hours, and then they just disconnected the call. I called back and held for almost 3 hours, then gave up, and I have opted for posting my review - online.