Hello, I accidently moved my egg from hatchery to stables. How do I fix this? Will something happen to egg? Thank you

Nothing going to happen it's still going to hatch it's just an option for you to move it to the Stables

Thank you, was worried

As an add on to what DeathWyvernSun said, moving the egg to the stables will have no effect on the egg at all.
A while back, an update was made to the Hatcheries where you could only sell a pet in the Hatchery on private sale(Where the pet is set to a specific User ID).
This update was partially made to help avoid people overbreeding pets and setting them up for sale, and having lots of pets released due to them being overbred by a user with little to no stable space left, leading to their pets being auto-released once they had reached adulthood.
The ability to move a pet from the Hatchery to Stables was done so that people would move the pets they wanted to sell to their stables, and put them on public sale, rather than do what was previously mentioned.

Your egg will still be nurtured just as much as it would have been in your Hatchery, it's just instead in your Stables. ^-^

It's true that nothing bad will happen to the Egg if it's just sitting in your Stables, Arcadiamoon. However, maybe you'd just prefer to have it back in the Hatchery? Leaving it in your Stables might cause it to receive fewer Nurtures from other players, so I can see why you'd prefer to have it back in your Hatchery.

If you do, there is a way to move it back. Simply get a friend to buy the Egg from you and then sell it right back to you. When you sell the Egg (or Hatchling, if it has hatched), it will automatically move into the other player's Hatchery. When you buy it again, it will move from their Hatchery to your Hatchery.