GPS RTK2 (ZED-F9P) problem with Base configuration

I am trying to implement a Base-Rover system using 2 x GFK RTK2

I can make the system work using u-center (the accuracy is amazing) but I am struggling to make the Base station work when driving it with a Teensy 3.6 and the StartRTCMBase example from the Sparkfun UBlox library

The unit reports “Survey Valid!” and “RTCM now broadcasting” but…

There is no activity on UART2 (I have set all messages to output on UART2)

The SFE_UBLOX_GPS::processRTCM function is never called…

Anyone have any ideas where to go next??

Many thanks

Donal

Hello i am facing the same issue . Do you happen to somehow sove this issue ? if yes then kindly guide me too

Thanks