Perhaps a superfllous comment, but have you tried
Nux Support?
As an (entirely satisfied) Nux B6 (but not Nux B6 Pro!) user, I've never had any reason to contact Nux support, But my expectation is that someone could guide you through the step-by-step process of 'pairing' your new new transmitter and receiver configuration,
TBH, I have no idea how 'Nux B6 pairing' works. I've just learned (from experience) that:
- it's better to let other instruments (e.g. guitars) that operate on the 2.4 Ghz Wireless band set up first and add my Nux transmitter/reviever connection later; My Nux B6 connection then automatically chooses a 'channel' within the 2.4Ghz. band that is 'not occupied' by other instruments
- powering up my 'receiver' first, followed by my 'transmitter' seems to work best, though I have no idea why
As a complete 'tech nerd' my assumption is that all B6/B6 Pro components have exactly the same wireless 'bandwidth'(2.4 Ghz) and exactly the same range of 'channels' within this bandwidth bso, in principle, they should be able to find each other,
The only problem I can think of is that (in your new confguration) your 'receiver' and 'transmitter' don't recognize each other's (in my words) "identification codes". So either your transmitter doesn't recognize your 'receiver' as 'paired'devices or the other waty round (or both).
Again, the only advice I can give is to contact 'Nux Support' on how to create/restore this 'pairing'.
Mike