I've got a problem with Pokemon Friendship level being reset after transferring it into Pokemon Home and then back into the same game. Here's some answers that I got from Pokemon Support on pokemon.com:
Me: "I've transferred several pokemon into Pokemon Home from Pokemon Sword and when I took them back (same game), their Friendship (Happiness) level decreased a lot, making me redo all camp stuff again to get it back."
Support: "If there are two users on a Nintendo Switch which both have save data and you have Pokémon friendship, but other user moves the Pokémon to their HOME box, then it would lose status."
Me: "I only have 1 user on my Switch. Same user, same game, transferred pokemon into Home for dex, then transferred them back straight after: friendship decreased (to base value, I suppose)"
...
Support: "The development team request specific examples of Pokémon that were affected by this (and also ones that weren't would be helpful), so that I can investigate further. More screenshot showing more information would be very helpful."
Me: "There is something strange happening with Friendship level of my Pokemon. At first I noticed that my Venusaur from Master Dojo and my Meowth from Early Purchase Event got their Friendship decreased, so I raised it back to maximim. Then I moved my other Pokemon into Home and back into Sword and some of them (Pikachu, Urshifu, Porygon-Z etc) lost their friendship level while others didn't. After repeating the process (Sword > Home > Sword) most of them to my surprise got their Friendship back, while my Slowbro (on screenshot above) and my Shiny Gyarados were still at basic value. And finally I raised their Friendship again to maximum and after transfering them into Home and back they remained at maximum. So I don't see any specific circumstances under which this bug occurs."
Support: "There are certain cases where a Pokemon's friendship level is reset, but we're not able to share information on exact specifications and settings."
Me: "So, can it be fixed?"
Support: "Support Team is unable to provide hints, tips, or tricks regarding standard or special gameplay. We recommend asking a friend, or using your favorite search engine to see if fellow trainers can assist you. Currently this is intended behavior and the development team will not elaborate any further. We are unable to assist any further and thank you for your understanding."
Has anyone run into the same problem? Any ideas why this is happening?