Chime and Floodlight problems

Hello, i'm a new member. I'm currently the owner of a 'Floodlight Cam' in the back garden. I also let my son share the floodlight on his phone. The problem is, is that i also have a Chime registered to him and his phone. Anyway, this all didn't seem to matter, nearly a year ago when my floodlight cam - in the Ring app - was set up to his Chime. For some reason this is no longer the case, even though both of us are still in shared mode on the floodlight cam. He is unable to share the chime with me as something seems to have gone a miss somewhere? He can't send an invite to my email to share the chime (ghosted), and when I try to set up my app with his chime it all works till it gets to linking the floodlight with the Chime and then it says "Updating firmware. This may take 5 minutes". Which it doesn't! When I press skip nothing happens and I have to do it again. He's even tried the same process of setting up the chime with my floodlight and the same thing happens. It's frustrating so can anyone help please? Regards H45