Boat device: multifunction sensor reader and publisher

I’m connecting vedirect to an ESP32 system, with shift level regulator.
The system collect many information about environment, GPS info and electric situation then publish all on MQTT and local display.
Everything works fine, collecting data from the vedirect of a BMV712 (serial port of ESP32)
The problem starts when I try to connect another vedirect device (MPPT 75/25): I connect the gnd together with the BVM and signal to different rx pin on ESP32, but the system crash
Do you know if there is a way to get the twos input in the same system?
I haven’t conected the 5v from vedirect

thank you