Arduino Primo: problem with ESP8266

I try Uart and SoftwareSerial still the same.

Schema Arduimo Primo = RX2 and TX2 are the pins 7 and 8.

EDIT: Connect ESP to nRF:

ESP nRF
U0TXD (26pin) -> nRF_RX2 (7 pin) (jumper option)
U0RXD (25pin) -> nRF_TX2 (8 pin) (jumper option)
GPIO5 (24 pin) -> nRF_RX2 (7 pin)