C099 F9P and M8N 5 Click GNSS: GPS NOT DETECTED

I am trying to use the C099 F9P and M8N 5 Click receivers with ardupilot on a Hex Cube Black. But the fc does not get information from the GPS (GPS: No GPS), as if I did not connect anything. With a Here + antenna if it works properly.

The only signals used are Tx and Rx (The receivers are supply externaly). I have tried swapping them one for another but I get the same result. The last parameters set in Ardupilot and uBlox are the following:

ARDUPILOT (V3.6.11)
GPS_TYPE: 2 (uBlox)
SERIAL3_BAUD: 38 (38400)

UBLOX (F9P and M8N) - PRT (Ports)
Target: 1 - UART1
Protocol in: 0 + 1 UBX + NMEA
Protocol out: 0 - UBX
Baudrate: 38400

I do not know if another parameter would have to be modified to establish a correct connection between uBlox and ARDUPILOT. Can anybody help me?