I am still experiencing severe issues when trying to connect to Realms.  I am not tech savvy, and the Nintendo Switch is not optimized for screen capture or sharing.  I cannot tell you how to reproduce my issues, and Mojang tweeted earlier today (yesterday?) that the connection issues people had been reporting were all solved now.  I report this just to make myself feel better.  I know Mojang is extremely big/busy.  I do not expect assistance.