A pending purchase will show estimated cashback in your feed, but the amount is not disbursed to your Venmo account until the charge is completed by the merchant. Once the transaction is complete, any earned cashback will be applied to your Venmo account.
I feel like QB and others are just too complicated for my needs, and the support is awful and confusing, but Less Accounting has much better support. Brian Elliot Gether.co I've been using the accounting software as well as the bookkeeping services for nearly seven years.