No watt on left pedal

Unfortunately I have a problem.

The device marks me connected both pedals but does not measure the watts from the left pedal.

What could it be?

Tests carried out:
- Connected both an Edge 810 and a Fenix ​​5x
- Changed batteries
-Sprayed spray for electric contacts, blown and cleaned all

Fw version 3.80

Both devices see the two pedals, but still 100% DX balance and half the watts ...

Help...