RSSI sensor lost in the multiprotocol module

[fdapport]

Hardware: Tandem X20s
Version Ethos: 1.5.19 FLEX
Multiprotocol Module Firmware V. 1.3.4.0
Receiver: RadioMaster R86 6chs, Frsky R8 protocol

All works ok, the only an unusual behavior is the RSSI sensor. If I search sensors I found the RSSI sensor but it is NOT showed in the top/right of the screen, see first picture.
If I delete the RSSI sensor from telemetry screen the RSSI indicator comes back in the top/right screen and also comes back the functionally of the lost sensors if I switch OFF the receiver. See second picture.
How it is possible this behavior? It is some thinks wrong in Ethos or in the Multiprotocol firmware?
It is some thinks that I need to configure in the telemetry sensors configuration?

[frankiearzu]

Is your TX close to the RX? Sometimes, when it is too close, it swamps the signal and causes telemetry to be lost. has to be 2' (50cm) or more away to have good signal.

[fdapport]

if you look the pictures the RSSI sensor could be ONLY on the Top Right screen OR in the list of the sensors, NOT in BOTH place as normal happen for internal RF module/Frsky receivers. Unfortunately the distance from TX and RX is NOT relevant for this issue