I was doing the new quests and trying to get all starter megastones. Blastoisinite went without problem but earlier today I caught a charmander which got accepted by oak so he told me to go and train it, so I bought the safari pass so i could ev train it fast and catch a bulbasaur right after. The charmander got ev trained and i caught a very good bulbasaur so I went back to oak and he asked me if I completed training with charmander, I selected the option to show another pokemon, the bulbasaur, it got accepted and he told me to go train it. I wanted to see if the charmander lost any progress so I talked to him again and showed him the charmander again. He said it has the right nature, but the IV's werent enough when earlier he said the charmander was good enough. I double checked if it wasn't the wrong one but no, its the right one.

Thanks in advance.

Update, the charmander did get accepted after obtaining the venusaurite.