Hey Alex,
If you are experiencing problems with the drone flying straight, try taking a look at the motors and propellers. If a propeller is damaged, it might cause the drone to fly strangely. If the propellers look okay, maybe you have a motor that isn't working properly. The motor will have to be replaced. Check out the [[Parrot Hydrofoil Orak Troubleshooting#Section_Drone_Won_t_Fly_Straight|troubleshooting page]] for the drone for some more details about why it isn't flying well.