Update: I feel it's fair to add that they did eventually resolve my problem - refunded the charge and issued me a credit for a free delivery. Took about a week to resolve the issue. I've used them a few times since (I guess I don't know when to quit) and haven't had another issue. Still a little bit of an alarming experience.
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I want to give Instacart a good review, because when it works it's a great service.
However, I wouldn't recommend giving them your business. I tried to place an order, there was an error with Instacart's site, and I got message telling me my payment had failed.
The charge still posted to my bank account. Never got groceries, never got as far as confirmation screen. Just gave Instacart $176.56 for nothing.
This was three days ago. There is no listed phone number to contact any kind of support for Instacart (go ahead, look for it), only an email address.
In three days, I have only gotten platitudes and put-offs from the customer service reps who answer that email address who seem unwilling or unable to understand the problem and assurances that "they understand my frustrations."
In the meantime, not only do I not have my groceries, I am also missing the money entirely until they get around to canceling the charge, so I can't use it to buy groceries elsewhere.
Great idea completely ruined by poorly tested software.