I set the transaction to cancelled but the pending status is “harmless” in the sense that the transaction was never completed at PayPal so you would have never been charged for it.
The store has to set the pending status because the payment processing happens on PayPal’s site and not ours. So, our store waits for PayPal to give the transaction completed status. After a bit of time of waiting, the payment automatically is marked abandoned. It has to be a longer period of time too since people do pay with echecks thru PayPal. The pending status has to remain available long enough for an echeck to clear (or not). Hope that make sense.