We're currently looking into why some players are seeing this, but please try the following as a potential work around for the issue:

1.  Fully close Bloons TD Battles 2+
2. Put your device in Flight Mode (so there is no internet connection)
3. Relaunch the game
4. From the game's main menu, tap on the menu icon (three lines at the top-right of the screen)
5. Tap "Go Online"
6. Then, once you see the "No internet connecton found." error, reconnect your device to the internet and hit "Try Again"

If this doesn't work, please submit a support request with all the details and we'll take a closer look!