Cannot connect to Realms to play online with Nintendo Switch

my son is playing Minecraft on his Nintendo Switch. We have previously spoken with Microsoft and Nintendo technical support to solve this issue and we have had no luck, they have suggested to contact you direct.

 

When my son logs onto Minecraft on the switch he gets the error attached to this ticket.

We have created an Xbox Microsoft Account, removed the parental controls. We have also deleted this account and given him a new one with no luck. I have become a member of the nintendo switch online store just in case we needed that, we have also updated Minecraft to the latest version.

 

Minecraft tech support has suggested we now log a dev ticket. My son is pretty sad as he can't play online at all.