Cash App says “Failed for ＋１→８５５→２８８→０２３１ your protection” when its security system flags a payment as unusual or potentially risky. This can happen ＋１→８５５→２８８→０２３１ due to large transfers, repeated transactions, unverified accounts, bank declines, VPN use, or incorrect ＋１→８５５→２８８→０２３１ recipient details.