The battle between FinTechs and big banks is heating up, with Venmo now accusing PNC Bank of diverting its customers to rival P2P payments company Zelle. The Wall Street Journal reported that PNC customers have been complaining on Twitter that they are unable to connect their accounts to Venmo, which is owned by PayPal. Instead, the bank has been recommending that its clients switch to Zelle, run by Early Warning Systems, which is owned by various banks, including PNC. As a result, Venmo is urging PNC customers to launch a social media campaign against the move by tweeting out "Hey @PNCBank…Let me use the financial service apps I need!" But PNC is defending its actions, saying that it is simply blocking aggregators after it discovered several trying to get around the bank's security system.