Cancelling Shipping Accessories?

Recently, I purchased a Nikon D7000 with a Nikkor 50mm f/1.4D lens (as an accessory) from Dell. There was a notice on the lens that it may be delayed by 9 days before shipping. Two days ago, I received my Nikon D7000 from the delivery truck, but I didn't received the lens, yet. However, I'm considering of cancelling the lens and just buying it straight from Best Buy (since I found out that they have it in stock).

Information
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Purchased from: Dell.
Purchased item: Nikon D7000 ($899) --> Arrived on Thurs. July 11, 2013.
Additional Accessory: 50mm f/1.8D lens ($350) ---> Still in delaying stage. 7 days left (excluding weekends).

Main Question: Is it possible to cancel the delivery of the accessory when I already received the purchased item? And will they also take out the price of the lens from the total amount once it's cancelled?

Messenger,

Yes, you can call and cancel the order. They will also credit your account. The number to call is
1-800-357-3355.

Thank you,
Dell-Jesse L
Dell Social Media and Communities