You have to go back to petalburg city and battle Norman/Your father.
go back to your fathers gym and defeat him
In sapphire, the 5th gym leader is your dad, in that city after Oakdale.
The 6th gym leader in Pokémon Sapphire is found at the Fortree Gym. The name of the gym leader here is Winona.
You have to Dive and then you can battle the Gym Leader.
The 8th Gym Leader in Pokémon Sapphire can be found in Sootopolis City.
The third gym leader in Pokemon Sapphire is Wattson and he is located in Mauville City.
The first 4 gyms are Rustboro City Gym leader Roxanne, Dewford Town Gym leader Brawly, Maulville City Gym leader Watson and Lavaridge Town Gym Leader.
In the Lavaridge Town gym.
In Lavaridge gym.
There in the gym in mossdeep city by the way the gym leader are actually gym leaders.
You can with AR.
In the lavaridge town gym.