You can still evolve it, but you'll have to check your clock in your room back in your house. It's stuck basically, so if it's an AM time, you can get Espeon and PM can get you Umbreon. But since the battery is dead, you can only get one of the two. Please use the Q&A thread next time. This section is getting so cluttered with locked threads ugh.
More specifically:
"Additionally, for no apparent reason, there is no way to change the clock for Daylight Savings Time in this generation. There was, however, some premise in the games. For example, Shoal Cave's water level would change every six hours, at 3:00 and 9:00 AM and PM. Just the same, Eevee would be able to evolve into Espeon if the in-game time was between 12:00 PM and 11:59 PM. Eevee would also be able to evolve into Umbreon if the in-game time was between 12:00 AM and 11:59 AM."
From Bulbapedia.
And as for tips, I'm assuming you mean happiness raising tips, obviously you wanna give Eevee the Soothe Bell. Feeding it vitamins helps, as does gaining a level (though if you want any Umbreon/Espeon specific moves, you might wanna just hold off on leveling past a certain level), and walking 256 will give a point for happiness as well. Using herbs lowers these points. And you can check happiness in Verdanturf. Some lady in a house etc.
Locked.
