So, this is not really a big problem but I though I should let you know just in case.
I got an error message just as I finished a battle. My connection was working perfectly fine, I checked!
That’s not really a big deal since rebooting the game fixed it, the battle counted as a win and I got my level up.
From the screenshot, you can see the game mentioning “downloading 1 of 2”, so I guess something went wrong while trying to download whatever it wanted to. Anyway, nothing important but I wanted to let you know just in case.